refactor: move admin dashboards to /admin namespace

- Move Oban Web from /oban to /admin/oban
- Move LiveDashboard from /dashboard to /admin/dashboard
- Both remain protected by :require_superuser plug
- Update documentation to reflect new paths

CLAUDE.md

@@ -223,13 +223,13 @@ LiveDashboard is available at `/dashboard` (requires authentication in productio
 Metrics are collected every 10 seconds via `telemetry_poller` and published using `:telemetry.execute/3`.
 
 To view metrics:
-1. Navigate to `/dashboard` (or `/dev/dashboard` in development)
+1. Navigate to `/admin/dashboard` (or `/dev/dashboard` in development)
 2. Click the "Metrics" tab
 3. Scroll to see Oban and Redis sections
 
 ### Oban Web Dashboard
 
-Oban Web provides a dedicated dashboard for job monitoring and management at `/oban` (superuser access required).
+Oban Web provides a dedicated dashboard for job monitoring and management at `/admin/oban` (superuser access required).
 
 **Access Control**: Only superusers can access the Oban Web dashboard. The route is protected by `:require_superuser` plug.
 
@@ -244,7 +244,7 @@ Oban Web provides a dedicated dashboard for job monitoring and management at `/o
 **Router Configuration**:
 ```elixir
 # lib/towerops_web/router.ex
-scope "/" do
+scope "/admin" do
   pipe_through [:browser, :require_authenticated_user, :require_superuser]
 
   oban_dashboard "/oban"

lib/towerops_web/router.ex

@@ -125,10 +125,10 @@ defmodule ToweropsWeb.Router do
   end
 
   # Enable LiveDashboard in production with authentication
-  scope "/dashboard" do
+  scope "/admin" do
     pipe_through [:browser, :require_authenticated_user, :require_superuser]
 
-    live_dashboard "/",
+    live_dashboard "/dashboard",
       metrics: ToweropsWeb.Telemetry,
       ecto_repos: [Towerops.Repo],
       ecto_psql_extras_options: [
@@ -140,7 +140,7 @@ defmodule ToweropsWeb.Router do
   end
 
   # Enable Oban Web (superuser only)
-  scope "/" do
+  scope "/admin" do
     pipe_through [:browser, :require_authenticated_user, :require_superuser]
 
     oban_dashboard("/oban")