fix(call): Wave-1 audit fixes (calls host side)

- C-H1: forceState only on FIRST join; on EC reconnect re-arm the fork handlers
  (resendForkState — deafen+quality only) instead of clobbering live mic/video/
  deafen back to the join-time snapshot.
- C-H2: AFK auto-mute reads the fork's io.lotus.call_state VAD of the LOCAL
  published track instead of getUserMedia on the browser DEFAULT mic (which could
  measure silence while the user spoke on another device → auto-mute an active
  speaker). Fails safe (never mutes) when call_state is null OR empty.
- C-H3: control observer re-binds after EC re-renders (body subtree:true + 100ms
  debounce) with an early-return so unchanged state doesn't re-render.
- C-M3 setQuality join-gated; C-M4 hangup 4s fallback dispose (idempotent);
  C-M5 PTT no longer silently un-deafens; C-M6 screenshare-audio mute resets on
  stop; C-L4 deafen key works in the iframe; C-L6 setState-after-unmount guards.

Reviewed (C-H2 [] fail-safe + C-H3 re-render guard applied). tsc/eslint/prettier
clean, build OK, 677 tests.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/plugins/call/CallEmbed.ts

@@ -57,6 +57,10 @@ export class CallEmbed {
 
   public joined = false;
 
+  // C-M4: set once dispose() has run so the hangup fallback timer can tell
+  // whether the embed was already torn down by the normal Close/Hangup echo.
+  public disposed = false;
+
   // [lotus #2] Latest per-participant state from io.lotus.call_state, or null
   // until the fork sends the first one. When non-null, the speaker/mute hooks
   // read it instead of scraping the EC iframe DOM.
@@ -403,6 +407,8 @@ export class CallEmbed {
    * @param opts
    */
   public dispose(): void {
+    if (this.disposed) return;
+    this.disposed = true;
     this.disposables.forEach((disposable) => {
       disposable();
     });
@@ -501,9 +507,19 @@ export class CallEmbed {
 
   private onCallJoined(): void {
     this.settleLoad();
-    this.joined = true;
     this.applyStyles();
     this.control.startObserving();
+
+    // C-H1: EC fires JoinCall again on an EC reconnect (this action has no
+    // once-guard). forceState() would reset live mic/video/deafen back to the
+    // join-time snapshot, so only run it on the FIRST join. On a rejoin we just
+    // re-apply styles/observers (above) and re-push the sticky fork state
+    // (deafen/quality), leaving the user's live media state untouched.
+    if (this.joined) {
+      this.control.resendForkState();
+      return;
+    }
+    this.joined = true;
     // EC ignores io.element.device_mute before join; re-apply desired state now that EC is live
     this.control.forceState(this.initialState);
   }