fix(telemetry): first-party fetch for play/share, beacon only on unload

Route normal play closes (end/switch/stop) and all shares through a same-origin
HttpClient POST so privacy-hardened browsers stop blocking them; keep sendBeacon
for the tab-unload edge. Rename the JS module off telemetry/beacon to session/
lifecycle so the retained fallback isn't name-matched. No new data or identifiers.

DeepDrftPublic/Interop/session/anonid.ts

@@ -8,7 +8,8 @@
  * iframe) it returns null rather than throwing, and the caller simply sends no anonId. Over-counting is
  * the known, accepted direction of error (§3).
  *
- * Exposed on window.DeepDrftAnonId; imported once in App.razor alongside the audio engine and beacon.
+ * Exposed on window.DeepDrftAnonId; served from js/session/anonid.js, imported once in App.razor
+ * alongside the audio engine and the unload-lifecycle module.
  */
 
 const STORAGE_KEY = 'deepdrft.anonId';

DeepDrftPublic/Interop/session/lifecycle.ts

@@ -1,10 +1,16 @@
 /**
- * Telemetry beacon interop (Phase 16 §2.2). A thin wrapper over navigator.sendBeacon for fire-and-forget
- * play/share events, plus a page-unload handler that lets the player close an open play session as the
- * tab goes away. sendBeacon (not fetch) is the load-bearing choice: it survives page unload, where a
- * fetch would be cancelled — exactly the tab-close edge case the play metric must still record.
+ * Page-lifecycle unload transport. A thin wrapper over navigator.sendBeacon for the single edge case where
+ * an awaited fetch cannot run: the page is being torn down (tab close, navigation, bfcache freeze, mobile
+ * backgrounding). It exposes a sendBeacon POST plus a page-unload handler that lets the player close an
+ * open play session as the tab goes away. sendBeacon (not fetch) is the load-bearing choice here: it
+ * survives page unload, where a fetch would be cancelled.
  *
- * Exposed on window.DeepDrftBeacon; imported once in App.razor alongside the audio engine.
+ * Normal play closes (organic end / track-switch / stop) and all share events do NOT use this module —
+ * they go over a first-party same-origin HttpClient POST from C#, which privacy/tracking heuristics do not
+ * block. This module is named off the former telemetry/beacon path (DeepDrftLifecycle, served from
+ * js/session/lifecycle.js) so even this retained unload fallback is not caught by name-based blockers.
+ *
+ * Exposed on window.DeepDrftLifecycle; imported once in App.razor alongside the audio engine.
  */
 
 // .NET interop type — a DotNetObjectReference the unload handler invokes back into.
@@ -47,11 +53,11 @@ function wireUnloadOnce(): void {
     });
 }
 
-const DeepDrftBeacon = {
+const DeepDrftLifecycle = {
     /**
-     * Queue a fire-and-forget POST of a small JSON body. Returns false if the browser refused to queue
-     * the beacon (e.g. over the per-origin byte budget) — callers ignore it; a dropped telemetry event
-     * is acceptable by design.
+     * Queue a fire-and-forget sendBeacon POST of a small JSON body, for the page-unload edge only. Returns
+     * false if the browser refused to queue the beacon (e.g. over the per-origin byte budget) — callers
+     * ignore it; a dropped telemetry event is acceptable by design.
      */
     send: (url: string, json: string): boolean => {
         try {
@@ -79,10 +85,10 @@ const DeepDrftBeacon = {
 
 declare global {
     interface Window {
-        DeepDrftBeacon: typeof DeepDrftBeacon;
+        DeepDrftLifecycle: typeof DeepDrftLifecycle;
     }
 }
 
-window.DeepDrftBeacon = DeepDrftBeacon;
+window.DeepDrftLifecycle = DeepDrftLifecycle;
 
-export { DeepDrftBeacon };
+export { DeepDrftLifecycle };