docs(api): add Coverages, Maintenance Windows, Schedules, Escalation Policies

The /docs/api and /docs/graphql pages were missing four resource
families that the API has shipped:

- Coverages (RF coverage prediction with async compute, recompute,
  KMZ download)
- Maintenance Windows (one-off + recurring with RRULE)
- On-Call Schedules (top-level CRUD + layers, members, overrides,
  on_call lookup)
- Escalation Policies (CRUD + rules + targets)

Both REST and GraphQL pages now have sidebar entries and example
requests for each.

lib/towerops_web/controllers/api_docs_html/index.html.heex

@@ -166,6 +166,42 @@
                 Graphs & Live Polling
               </a>
             </li>
+            <li>
+              <a
+                href="#coverages"
+                data-nav-link="coverages"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                RF Coverages
+              </a>
+            </li>
+            <li>
+              <a
+                href="#maintenance-windows"
+                data-nav-link="maintenance-windows"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Maintenance Windows
+              </a>
+            </li>
+            <li>
+              <a
+                href="#schedules"
+                data-nav-link="schedules"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                On-Call Schedules
+              </a>
+            </li>
+            <li>
+              <a
+                href="#escalation-policies"
+                data-nav-link="escalation-policies"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Escalation Policies
+              </a>
+            </li>
           </ul>
         </li>
         
@@ -3864,6 +3900,506 @@ curl -G https://towerops.net/api/v1/activity \\
 
       <hr class="my-16 border-gray-200 dark:border-white/10" />
       
+<!-- Coverages Resource -->
+      <section id="coverages" class="scroll-mt-24 mb-16">
+        <h2 class="text-3xl font-bold tracking-tight text-zinc-900 dark:text-white">
+          RF Coverages
+        </h2>
+        <p class="mt-4 text-base text-gray-600 dark:text-gray-400">
+          RF coverage predictions model where each radio actually reaches. Compute is async — a created or recomputed coverage starts in
+          <code>queued</code>
+          and progresses through <code>computing</code>
+          to <code>ready</code>
+          or <code>failed</code>. The status field is present on every response so polling-based clients (Terraform, Ansible, scripts) can wait for a healthy resource. Outputs include a coloured PNG heatmap, a Float32 GeoTIFF raster, and a downloadable KMZ bundle for Google Earth.
+        </p>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">List all coverages</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>GET /api/v1/coverages</code>. Returns every coverage in the authenticated organization, regardless of status.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl -G https://towerops.net/api/v1/coverages \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Create a coverage</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>POST /api/v1/coverages</code>. Creates a new coverage and immediately enqueues compute. Required: <code>name</code>, <code>site_id</code>, <code>antenna_slug</code>, <code>frequency_mhz</code>, <code>tx_power_dbm</code>, <code>height_agl_m</code>, <code>azimuth_deg</code>, <code>radius_m</code>. Optional fields tune cell size, downtilt, foliage, receiver height, and threshold.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/coverages \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "coverage": {
+      "name": "North sector 5 GHz",
+      "site_id": "550e8400-e29b-41d4-a716-446655440000",
+      "antenna_slug": "rf-elements-twistport-symmetrical-horn-30",
+      "frequency_mhz": 5800,
+      "tx_power_dbm": 22.0,
+      "height_agl_m": 30,
+      "azimuth_deg": 0,
+      "downtilt_deg": 2,
+      "radius_m": 6000,
+      "cell_size_m": 10
+    }
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Retrieve a coverage</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>GET /api/v1/coverages/:id</code>. Returns one coverage including its bbox, status, progress percentage, and (when ready) the
+                <code>png_path</code>
+                + <code>raster_path</code>
+                outputs.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl https://towerops.net/api/v1/coverages/COV_ID \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Update a coverage</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>PATCH /api/v1/coverages/:id</code>. Mutates editable fields (name, antenna parameters, radius, cell size, etc.). Does
+                <strong>not</strong>
+                auto-recompute — call the recompute endpoint when you want fresh outputs.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X PATCH https://towerops.net/api/v1/coverages/COV_ID \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{"coverage": {"tx_power_dbm": 25.0}}'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">
+            Recompute a coverage
+          </h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>POST /api/v1/coverages/:id/recompute</code>. Re-queues the compute pipeline without changing any parameters. Returns
+                <code>409 Conflict</code>
+                if the coverage is already computing. Useful after a parameter update or after the antenna catalog is refreshed.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl -X POST https://towerops.net/api/v1/coverages/COV_ID/recompute \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Download as KMZ</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>GET /api/v1/coverages/:id/kmz</code>. Returns a Google Earth-compatible KMZ bundle (KML + PNG). Returns
+                <code>409 Conflict</code>
+                if the coverage is not yet ready.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl -OJ https://towerops.net/api/v1/coverages/COV_ID/kmz \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Delete a coverage</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>DELETE /api/v1/coverages/:id</code>. Removes the coverage and any cached outputs. Returns
+                <code>204 No Content</code>
+                on success.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl -X DELETE https://towerops.net/api/v1/coverages/COV_ID \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+      </section>
+
+      <hr class="my-16 border-gray-200 dark:border-white/10" />
+      
+<!-- Maintenance Windows Resource -->
+      <section id="maintenance-windows" class="scroll-mt-24 mb-16">
+        <h2 class="text-3xl font-bold tracking-tight text-zinc-900 dark:text-white">
+          Maintenance Windows
+        </h2>
+        <p class="mt-4 text-base text-gray-600 dark:text-gray-400">
+          Maintenance windows tell Towerops to suppress alerts for a site or device during planned work. Windows can be one-off or recurring (iCal RRULE).
+        </p>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">
+            List maintenance windows
+          </h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>GET /api/v1/maintenance_windows</code>. Optional <code>filter</code>
+                query param accepts <code>active</code>, <code>upcoming</code>, or <code>past</code>.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl -G https://towerops.net/api/v1/maintenance_windows \\
+  -H "Authorization: Bearer #{@sample_token}" \\
+  -d filter=active
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">
+            Create a maintenance window
+          </h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>POST /api/v1/maintenance_windows</code>. Required: <code>name</code>, <code>starts_at</code>, <code>ends_at</code>. Scope to a site or a specific device. Set
+                <code>recurring: true</code>
+                with a <code>recurrence_rule</code>
+                (RRULE) to repeat.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/maintenance_windows \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "maintenance_window": {
+      "name": "Quarterly firmware roll",
+      "starts_at": "2026-06-01T05:00:00Z",
+      "ends_at":   "2026-06-01T09:00:00Z",
+      "site_id":   "SITE_UUID",
+      "suppress_alerts": true
+    }
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">
+            Get / update / delete
+          </h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                Standard CRUD on <code>/api/v1/maintenance_windows/:id</code>. <code>GET</code>
+                returns the resource; <code>PATCH</code>
+                updates fields with the same body shape as create; <code>DELETE</code>
+                returns a JSON success body.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl -X DELETE https://towerops.net/api/v1/maintenance_windows/WINDOW_ID \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+      </section>
+
+      <hr class="my-16 border-gray-200 dark:border-white/10" />
+      
+<!-- Schedules Resource -->
+      <section id="schedules" class="scroll-mt-24 mb-16">
+        <h2 class="text-3xl font-bold tracking-tight text-zinc-900 dark:text-white">
+          On-Call Schedules
+        </h2>
+        <p class="mt-4 text-base text-gray-600 dark:text-gray-400">
+          Schedules drive who gets paged when an alert fires. A schedule contains one or more
+          <em>layers</em>
+          (rotations); each layer has ordered <em>members</em>. Ad-hoc <em>overrides</em>
+          let you swap the on-call user for a fixed time window without changing the rotation.
+        </p>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Schedule CRUD</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>GET /api/v1/schedules</code>, <code>POST</code>, <code>GET /:id</code>, <code>PATCH /:id</code>, <code>DELETE /:id</code>. Required on create: <code>name</code>, <code>timezone</code>. Showing one schedule returns its layers + overrides nested.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/schedules \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "schedule": {
+      "name": "Primary on-call",
+      "description": "Weekly rotation",
+      "timezone": "America/Chicago"
+    }
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Who is on call?</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>GET /api/v1/schedules/:id/on_call</code>. Returns the user currently on call (taking layers and overrides into account), or
+                <code>null</code>
+                if nobody is.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw("""
+curl https://towerops.net/api/v1/schedules/SCHED_ID/on_call \\
+  -H "Authorization: Bearer #{@sample_token}"
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Layers and members</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>POST /api/v1/schedules/:id/layers</code>, <code>PATCH /api/v1/schedules/:id/layers/:layer_id</code>,
+                <code>DELETE</code>
+                the same. A layer requires <code>name</code>, <code>position</code>,
+                <code>rotation_type</code>
+                (<code>weekly</code>/<code>daily</code>/<code>custom</code>), <code>rotation_interval</code>, <code>handoff_time</code>, and <code>start_date</code>.
+                <br /><br /> Add and remove members with
+                <code>POST /:id/layers/:layer_id/members</code>
+                (body: <code>user_id</code>, <code>position</code>) and <code>DELETE /:id/layers/:layer_id/members/:member_id</code>.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/schedules/SCHED_ID/layers \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "layer": {
+      "name": "Primary",
+      "position": 0,
+      "rotation_type": "weekly",
+      "rotation_interval": 1,
+      "handoff_time": "09:00:00",
+      "start_date": "2026-06-01T00:00:00Z"
+    }
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Overrides</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>POST /api/v1/schedules/:id/overrides</code>
+                creates a one-off cover ("Bob is on for Alice from Friday 17:00 to Monday 09:00"). Required: <code>user_id</code>, <code>start_time</code>, <code>end_time</code>. Remove with <code>DELETE /:id/overrides/:override_id</code>.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/schedules/SCHED_ID/overrides \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "override": {
+      "user_id": "USER_UUID",
+      "start_time": "2026-06-07T17:00:00Z",
+      "end_time":   "2026-06-09T09:00:00Z"
+    }
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+      </section>
+
+      <hr class="my-16 border-gray-200 dark:border-white/10" />
+      
+<!-- Escalation Policies Resource -->
+      <section id="escalation-policies" class="scroll-mt-24 mb-16">
+        <h2 class="text-3xl font-bold tracking-tight text-zinc-900 dark:text-white">
+          Escalation Policies
+        </h2>
+        <p class="mt-4 text-base text-gray-600 dark:text-gray-400">
+          Escalation policies are an ordered list of <em>rules</em>; each rule fires its
+          <em>targets</em>
+          after a delay if the previous rule's targets haven't acknowledged the alert. Targets can reference users, schedules, or arbitrary webhooks.
+        </p>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Policy CRUD</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                Standard REST CRUD under <code>/api/v1/escalation_policies</code>.
+                <code>GET /:id</code>
+                returns the policy with its rules and targets nested. Required on create: <code>name</code>. Optional: <code>description</code>, <code>repeat_count</code>, <code>repeat_interval_minutes</code>.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/escalation_policies \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "escalation_policy": {
+      "name": "Critical alerts",
+      "description": "Page primary, then secondary, then manager",
+      "repeat_count": 3,
+      "repeat_interval_minutes": 15
+    }
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Rules</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                <code>POST /api/v1/escalation_policies/:id/rules</code>
+                appends a rule. <code>PATCH /api/v1/escalation_policies/:id/rules/:rule_id</code>
+                updates one. <code>DELETE</code>
+                removes one. Required on create: <code>position</code>, <code>delay_minutes</code>.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/escalation_policies/POLICY_ID/rules \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "rule": {"position": 0, "delay_minutes": 5}
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+
+        <div class="mt-12">
+          <h3 class="text-xl font-semibold text-zinc-900 dark:text-white">Targets</h3>
+          <div class="mt-4 grid grid-cols-1 gap-x-8 gap-y-4 lg:grid-cols-2">
+            <div>
+              <p class="text-base text-gray-600 dark:text-gray-400">
+                Each rule has one or more targets:
+                <code>POST /api/v1/escalation_policies/:id/rules/:rule_id/targets</code>
+                creates one,
+                <code>
+                  DELETE /api/v1/escalation_policies/:id/rules/:rule_id/targets/:target_id
+                </code>
+                removes it. A target body specifies <code>target_type</code>
+                (<code>user</code>, <code>schedule</code>, or <code>webhook</code>) plus the corresponding identifier or URL.
+              </p>
+            </div>
+            <div>
+              <div class="overflow-hidden rounded-lg bg-gray-900 dark:bg-gray-950">
+                <pre class="p-4 text-sm text-zinc-100 overflow-x-auto"><code><%= raw(~S"""
+curl -X POST https://towerops.net/api/v1/escalation_policies/POLICY_ID/rules/RULE_ID/targets \
+  -H "Authorization: Bearer YOUR_API_TOKEN" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "target": {"target_type": "schedule", "schedule_id": "SCHED_UUID"}
+  }'
+""") %></code></pre>
+              </div>
+            </div>
+          </div>
+        </div>
+      </section>
+
+      <hr class="my-16 border-gray-200 dark:border-white/10" />
+      
 <!-- Terraform Provider Section -->
       <section id="terraform" class="scroll-mt-24 mb-16">
         <h2 class="text-3xl font-bold tracking-tight text-zinc-900 dark:text-white">

lib/towerops_web/controllers/graphql_docs_html/index.html.heex

@@ -126,6 +126,38 @@
                 Time-Series
               </a>
             </li>
+            <li>
+              <a
+                href="#query-checks"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Service Checks
+              </a>
+            </li>
+            <li>
+              <a
+                href="#query-schedules"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                On-Call Schedules
+              </a>
+            </li>
+            <li>
+              <a
+                href="#query-escalation-policies"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Escalation Policies
+              </a>
+            </li>
+            <li>
+              <a
+                href="#query-maintenance-windows"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Maintenance Windows
+              </a>
+            </li>
           </ul>
         </li>
         
@@ -189,6 +221,38 @@
                 Integrations
               </a>
             </li>
+            <li>
+              <a
+                href="#mutation-checks"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Service Checks
+              </a>
+            </li>
+            <li>
+              <a
+                href="#mutation-schedules"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Schedules
+              </a>
+            </li>
+            <li>
+              <a
+                href="#mutation-escalation-policies"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Escalation Policies
+              </a>
+            </li>
+            <li>
+              <a
+                href="#mutation-maintenance-windows"
+                class="nav-link block py-1 pl-4 pr-3 text-sm text-gray-600 transition hover:text-gray-900 dark:text-gray-400 dark:hover:text-white"
+              >
+                Maintenance Windows
+              </a>
+            </li>
           </ul>
         </li>
         
@@ -841,6 +905,179 @@
       </div>
     </section>
     
+<!-- Queries: Service Checks -->
+    <section id="query-checks" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Query: Service Checks
+      </h2>
+      <p class="mt-2 text-base text-gray-600 dark:text-gray-400">
+        List and inspect HTTP, TCP, DNS, and ping service checks.
+      </p>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">checks</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  checks(checkType: "http", deviceId: "device-uuid") {
+    id
+    name
+    checkType
+    enabled
+    intervalSeconds
+    currentState
+    config
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">check (single)</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  check(id: "check-uuid") {
+    id
+    name
+    checkType
+    config
+    currentState
+    currentStateType
+    lastCheckAt
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
+<!-- Queries: Schedules -->
+    <section id="query-schedules" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Query: On-Call Schedules
+      </h2>
+      <p class="mt-2 text-base text-gray-600 dark:text-gray-400">
+        Inspect schedules and find out who is currently on call.
+      </p>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">schedules</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  schedules {
+    id
+    name
+    timezone
+    description
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">
+        schedule (with layers + overrides)
+      </h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  schedule(id: "schedule-uuid") {
+    id
+    name
+    timezone
+    layers {
+      id
+      name
+      position
+      rotationType
+      members {
+        userId
+        position
+      }
+    }
+    overrides {
+      id
+      userId
+      startTime
+      endTime
+    }
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">onCall</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  onCall(scheduleId: "schedule-uuid") {
+    userId
+    email
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
+<!-- Queries: Escalation Policies -->
+    <section id="query-escalation-policies" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Query: Escalation Policies
+      </h2>
+      <p class="mt-2 text-base text-gray-600 dark:text-gray-400">
+        Inspect escalation policies and their rules + targets.
+      </p>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">escalationPolicies</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  escalationPolicies {
+    id
+    name
+    description
+    repeatCount
+    repeatIntervalMinutes
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">
+        escalationPolicy (with rules + targets)
+      </h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  escalationPolicy(id: "policy-uuid") {
+    id
+    name
+    rules {
+      id
+      position
+      delayMinutes
+      targets {
+        id
+        targetType
+        userId
+        scheduleId
+      }
+    }
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
+<!-- Queries: Maintenance Windows -->
+    <section id="query-maintenance-windows" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Query: Maintenance Windows
+      </h2>
+      <p class="mt-2 text-base text-gray-600 dark:text-gray-400">
+        Inspect planned and active maintenance windows. The optional <code>filter</code>
+        argument accepts <code>active</code>, <code>upcoming</code>, or <code>past</code>.
+      </p>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">maintenanceWindows</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[{
+  maintenanceWindows(filter: "upcoming") {
+    id
+    name
+    startsAt
+    endsAt
+    suppressAlerts
+    siteId
+    deviceId
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
 <!-- Mutations: Devices -->
     <section id="mutation-devices" class="mb-16">
       <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
@@ -1070,6 +1307,224 @@ mutation { cancelInvitation(id: "invitation-uuid") { success message } }]) %></c
       </div>
     </section>
     
+<!-- Mutations: Service Checks -->
+    <section id="mutation-checks" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Mutation: Service Checks
+      </h2>
+
+      <h3 class="mt-6 text-lg font-semibold text-zinc-900 dark:text-white">createCheck</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createCheck(input: {
+    name: "API health"
+    checkType: "http"
+    deviceId: "device-uuid"
+    intervalSeconds: 60
+    config: {url: "https://api.example.com/health", method: "GET"}
+  }) {
+    id
+    name
+    checkType
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">
+        updateCheck / deleteCheck
+      </h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  updateCheck(id: "check-uuid", input: {intervalSeconds: 30}) {
+    id
+    intervalSeconds
+  }
+}
+
+mutation {
+  deleteCheck(id: "check-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
+<!-- Mutations: Schedules -->
+    <section id="mutation-schedules" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Mutation: Schedules
+      </h2>
+
+      <h3 class="mt-6 text-lg font-semibold text-zinc-900 dark:text-white">Schedule CRUD</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createSchedule(input: {
+    name: "Primary on-call"
+    timezone: "America/Chicago"
+  }) {
+    id
+    name
+  }
+}
+
+mutation {
+  updateSchedule(id: "schedule-uuid", input: {description: "Weekly rotation"}) {
+    id
+    description
+  }
+}
+
+mutation {
+  deleteSchedule(id: "schedule-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">Layers + members</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createLayer(scheduleId: "schedule-uuid", input: {
+    name: "Primary"
+    position: 0
+    rotationType: "weekly"
+    rotationInterval: 1
+    handoffTime: "09:00:00"
+    startDate: "2026-06-01T00:00:00Z"
+  }) {
+    id
+  }
+}
+
+mutation {
+  addLayerMember(layerId: "layer-uuid", userId: "user-uuid", position: 0) {
+    id
+  }
+}
+
+mutation {
+  removeLayerMember(id: "member-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">Overrides</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createOverride(scheduleId: "schedule-uuid", input: {
+    userId: "user-uuid"
+    startTime: "2026-06-07T17:00:00Z"
+    endTime:   "2026-06-09T09:00:00Z"
+  }) {
+    id
+  }
+}
+
+mutation {
+  deleteOverride(id: "override-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
+<!-- Mutations: Escalation Policies -->
+    <section id="mutation-escalation-policies" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Mutation: Escalation Policies
+      </h2>
+
+      <h3 class="mt-6 text-lg font-semibold text-zinc-900 dark:text-white">Policy CRUD</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createEscalationPolicy(input: {
+    name: "Critical alerts"
+    repeatCount: 3
+    repeatIntervalMinutes: 15
+  }) {
+    id
+    name
+  }
+}
+
+mutation {
+  updateEscalationPolicy(id: "policy-uuid", input: {name: "Critical alerts (revised)"}) {
+    id
+  }
+}
+
+mutation {
+  deleteEscalationPolicy(id: "policy-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+
+      <h3 class="mt-8 text-lg font-semibold text-zinc-900 dark:text-white">Rules + targets</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createEscalationRule(escalationPolicyId: "policy-uuid", input: {
+    position: 0
+    delayMinutes: 5
+  }) {
+    id
+  }
+}
+
+mutation {
+  createEscalationTarget(escalationRuleId: "rule-uuid", input: {
+    targetType: "schedule"
+    scheduleId: "schedule-uuid"
+  }) {
+    id
+  }
+}
+
+mutation {
+  deleteEscalationTarget(id: "target-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
+<!-- Mutations: Maintenance Windows -->
+    <section id="mutation-maintenance-windows" class="mb-16">
+      <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">
+        Mutation: Maintenance Windows
+      </h2>
+
+      <h3 class="mt-6 text-lg font-semibold text-zinc-900 dark:text-white">CRUD</h3>
+      <div class="mt-4 rounded-lg bg-zinc-900 p-4 dark:bg-zinc-800">
+        <pre class="text-sm text-green-400 overflow-x-auto"><code><%= raw(~S[mutation {
+  createMaintenanceWindow(input: {
+    name: "Quarterly firmware roll"
+    startsAt: "2026-06-01T05:00:00Z"
+    endsAt:   "2026-06-01T09:00:00Z"
+    siteId: "site-uuid"
+    suppressAlerts: true
+  }) {
+    id
+    name
+  }
+}
+
+mutation {
+  updateMaintenanceWindow(id: "window-uuid", input: {endsAt: "2026-06-01T10:00:00Z"}) {
+    id
+    endsAt
+  }
+}
+
+mutation {
+  deleteMaintenanceWindow(id: "window-uuid") {
+    success
+  }
+}]) %></code></pre>
+      </div>
+    </section>
+    
 <!-- Subscriptions -->
     <section id="subscriptions" class="mb-16">
       <h2 class="text-2xl font-bold tracking-tight text-zinc-900 dark:text-white">