Improve path page UX: prominent GPS button, share links

- "My Location" button with text label (was just an icon)
- Two share buttons after results:
  - "Copy Link" — fixed coordinates, exact result
  - "Copy Link (use viewer's GPS)" — source=gps, dynamic per viewer
- CopyLink JS hook copies full URL to clipboard with "Copied!" feedback

assets/js/app.js

@@ -35,7 +35,7 @@ import {ContactMap} from "./contact_map_hook"
 import {ContactsMap} from "./contacts_map_hook"
 import {ElevationProfile} from "./elevation_profile_hook"
 import {WeatherMap} from "./weather_map_hook"
-import {LocateMe} from "./locate_me_hook"
+import {LocateMe, CopyLink} from "./locate_me_hook"
 
 const UtcClock = {
   mounted() {
@@ -57,7 +57,7 @@ const csrfToken = document.querySelector("meta[name='csrf-token']").getAttribute
 const liveSocket = new LiveSocket("/live", Socket, {
   longPollFallbackMs: 2500,
   params: initLiveStash({_csrf_token: csrfToken}),
-  hooks: {...colocatedHooks, PropagationMap, UtcClock, ContactMap, ContactsMap, ElevationProfile, WeatherMap, LocateMe},
+  hooks: {...colocatedHooks, PropagationMap, UtcClock, ContactMap, ContactsMap, ElevationProfile, WeatherMap, LocateMe, CopyLink},
 })
 
 // Show progress bar on live navigation and form submits

assets/js/locate_me_hook.js

@@ -1,3 +1,16 @@
+export const CopyLink = {
+  mounted() {
+    this.el.addEventListener("click", () => {
+      const url = window.location.origin + this.el.dataset.url
+      navigator.clipboard.writeText(url).then(() => {
+        const orig = this.el.innerHTML
+        this.el.innerHTML = '<span class="text-success">Copied!</span>'
+        setTimeout(() => { this.el.innerHTML = orig }, 1500)
+      })
+    })
+  }
+}
+
 export const LocateMe = {
   mounted() {
     this.el.addEventListener("click", () => this.locate())

lib/microwaveprop_web/live/path_live.ex

@@ -470,6 +470,27 @@ defmodule MicrowavepropWeb.PathLive do
   defp format_utc_hour(%DateTime{} = dt), do: Calendar.strftime(dt, "%H:%M")
   defp format_utc_hour(_), do: "?"
 
+  defp share_url(result, mode) do
+    source =
+      case mode do
+        :gps -> "gps"
+        :fixed -> "#{Float.round(result.source.lat, 4)},#{Float.round(result.source.lon, 4)}"
+      end
+
+    params = %{
+      "source" => source,
+      "destination" => result.destination.label,
+      "band" => to_string(result.band_mhz),
+      "src_height_ft" => to_string(result.station_params.src_height_ft),
+      "dst_height_ft" => to_string(result.station_params.dst_height_ft),
+      "tx_power_dbm" => to_string(result.station_params.tx_power_dbm),
+      "src_gain_dbi" => to_string(result.station_params.src_gain_dbi),
+      "dst_gain_dbi" => to_string(result.station_params.dst_gain_dbi)
+    }
+
+    "/path?" <> URI.encode_query(params)
+  end
+
   defp format_mw(mw) when mw >= 1000, do: "#{format_number(mw / 1000)} W"
   defp format_mw(mw) when mw >= 1, do: "#{format_number(mw)} mW"
   defp format_mw(mw), do: "#{format_number(mw * 1000)} uW"
@@ -488,25 +509,24 @@ defmodule MicrowavepropWeb.PathLive do
       <form phx-submit="calculate" phx-change="update_form" class="bg-base-200 rounded-box p-4 mb-6">
         <div class="grid grid-cols-1 md:grid-cols-4 gap-4 items-end">
           <div class="fieldset">
-            <label class="label text-sm font-medium">Source (callsign or grid)</label>
+            <label class="label text-sm font-medium">Source</label>
             <div class="flex gap-1">
               <input
                 type="text"
                 name="source"
                 id="source-input"
                 value={@source}
-                placeholder="W5ISP or EM13sf"
+                placeholder="W5ISP, EM13sf, or lat,lon"
                 class="input input-bordered flex-1"
-                required
               />
               <button
                 type="button"
                 id="locate-me"
                 phx-hook="LocateMe"
-                class="btn btn-square btn-sm btn-ghost"
-                title="Use GPS location"
+                class="btn btn-sm btn-outline gap-1"
+                title="Use device GPS"
               >
-                <.icon name="hero-map-pin" class="size-4" />
+                <.icon name="hero-map-pin" class="size-3.5" /> My Location
               </button>
             </div>
           </div>
@@ -896,6 +916,28 @@ defmodule MicrowavepropWeb.PathLive do
         </div>
       </div>
     <% end %>
+
+    <%!-- Share links --%>
+    <div class="flex flex-wrap gap-2 mb-6">
+      <button
+        type="button"
+        phx-hook="CopyLink"
+        id="copy-link"
+        data-url={share_url(@result, :fixed)}
+        class="btn btn-sm btn-outline gap-1"
+      >
+        <.icon name="hero-link" class="size-3.5" /> Copy Link
+      </button>
+      <button
+        type="button"
+        phx-hook="CopyLink"
+        id="copy-gps-link"
+        data-url={share_url(@result, :gps)}
+        class="btn btn-sm btn-outline gap-1"
+      >
+        <.icon name="hero-map-pin" class="size-3.5" /> Copy Link (use viewer's GPS)
+      </button>
+    </div>
     """
   end