fix(lotus): Wave-1 audit fixes (EC1–EC6)

- EC1: lotusQuality — track + clearTimeout the 500ms settle re-apply per room
  (was leaking a timer that fired on torn-down rooms).
- EC2/EC3: lotusQuality + lotusAudioInject drive off vm.allConnections$ instead
  of the remote-gated livekitRoomItems$ (were no-ops when alone), matching
  lotusDenoise.
- EC4: lotusDecorations resets its roster to {} on teardown so a decoration from
  a previous call can't render on a shared user in the next one.
- EC5: hoisted a stable useSyncExternalStore subscribe fn (was re-subscribing
  every tile render).
- EC6: lotusFocus only sets the spotlight when the userId field is present
  (a partial payload no longer clears the pin).

tsc clean. Needs a republish to ship.

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

src/lotus/lotusQuality.ts

@@ -48,6 +48,10 @@ export function startLotusQuality(vm: CallViewModel): () => void {
   // Per-room LocalTrackPublished listeners, so sticky settings re-apply on
   // every (re)publish.
   const roomListeners = new Map<LivekitRoom, () => void>();
+  // Per-room settle re-apply timers, so we can cancel a pending 500ms re-apply
+  // when a room is removed or on teardown — otherwise it would fire against a
+  // torn-down room.
+  const settleTimers = new Map<LivekitRoom, ReturnType<typeof setTimeout>>();
   let rooms: LivekitRoom[] = [];
 
   const applyToRoom = (room: LivekitRoom): void => {
@@ -76,8 +80,12 @@ export function startLotusQuality(vm: CallViewModel): () => void {
   const applyToAll = (): void => rooms.forEach(applyToRoom);
 
   // Keep the LocalTrackPublished listeners in sync with the connected rooms.
-  const sub = vm.livekitRoomItems$.subscribe((items) => {
-    const next = items.map((i) => i.livekitRoom);
+  // Drive off the LOCAL participant's connection(s), not `livekitRoomItems$` —
+  // that stream omits rooms with no remote members (returns null for isLocal),
+  // so caps wouldn't apply to the local senders while you're alone. Map the
+  // connections to their livekit rooms exactly like `lotusDenoise.ts` does.
+  const sub = vm.allConnections$.subscribe((data) => {
+    const next = data.getConnections().map((c) => c.livekitRoom);
     rooms = next;
     // Remove listeners for rooms that went away.
     for (const [room, off] of roomListeners) {
@@ -97,7 +105,18 @@ export function startLotusQuality(vm: CallViewModel): () => void {
         // recompute so our cap wins.
         const reapply = (): void => {
           applyToRoom(room);
-          setTimeout(() => applyToRoom(room), 500);
+          // Store the settle timer per room and cancel any pending one, so it
+          // can be cleared on removal/teardown and never fires against a
+          // torn-down room.
+          const prev = settleTimers.get(room);
+          if (prev !== undefined) clearTimeout(prev);
+          settleTimers.set(
+            room,
+            setTimeout(() => {
+              settleTimers.delete(room);
+              applyToRoom(room);
+            }, 500),
+          );
         };
         const events = [
           ParticipantEvent.LocalTrackPublished,
@@ -106,6 +125,9 @@ export function startLotusQuality(vm: CallViewModel): () => void {
         for (const e of events) room.localParticipant.on(e, reapply);
         roomListeners.set(room, () => {
           for (const e of events) room.localParticipant.off(e, reapply);
+          const t = settleTimers.get(room);
+          if (t !== undefined) clearTimeout(t);
+          settleTimers.delete(room);
         });
         applyToRoom(room);
       }