debug(nests): wire NestRx/NestTx logs across listener and speaker paths

Diagnostic instrumentation to localise the listener-stuck-on-spinner bug.
None of these are intended for merge — pair logs with a logcat capture,
diagnose, then revert.

Receiver (tag NestRx):
  - MoqLiteNestsListener: log subscribeSpeaker / subscribeCatalog entry
    and per-update RoomAnnouncement emission to the VM
  - MoqLiteSession.subscribe: log SUBSCRIBE_OK / SUBSCRIBE_DROP outcomes
  - MoqLiteSession.drainOneGroup: log every uni group header decode
    and warn on subscription-lookup miss (frame dropped)
  - MoqLiteSession.pumpAnnounceWatch: log every announce update and
    flag the Ended branch that closes the subscription's frames
  - NestViewModel: log VM.openSubscription wiring and the first-frame
    trigger that clears the connectingSpeakers spinner

Speaker (tag NestTx):
  - MoqLiteSession.publish: log entry suffix
  - MoqLiteSession.handleInboundBidi: log inbound AnnouncePlease and
    SUBSCRIBE dispatches plus FIN cleanup
  - MoqLiteSession PublisherStateImpl: log first inbound subscriber
    attach and every group-stream open
  - NestMoqLiteBroadcaster: log when publisher.send returns false
    (no inbound subscriber on relay) and the subscriber-attached
    transition, plus surface throws that runCatching previously
    swallowed only into onError

Capture with `adb logcat -s NestRx:D NestTx:D`.

https://claude.ai/code/session_01PYYez8a6sjiakyjAxsfCEQ

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/viewmodels/NestViewModel.kt

@@ -44,6 +44,7 @@ import com.vitorpamplona.nestsclient.moq.SubscribeHandle
 import com.vitorpamplona.nestsclient.transport.WebTransportFactory
 import com.vitorpamplona.quartz.nip01Core.signers.NostrSigner
 import com.vitorpamplona.quartz.nip53LiveActivities.chat.LiveActivitiesChatMessageEvent
+import com.vitorpamplona.quartz.utils.Log
 import kotlinx.collections.immutable.ImmutableSet
 import kotlinx.collections.immutable.persistentSetOf
 import kotlinx.collections.immutable.toPersistentSet
@@ -842,7 +843,9 @@ class NestViewModel(
     ) {
         if (closed || activeSubscriptions[pubkey] !== slot) return
         try {
+            Log.d("NestRx") { "VM.openSubscription -> subscribeSpeaker pubkey=$pubkey" }
             val handle = l.subscribeSpeaker(pubkey)
+            Log.d("NestRx") { "VM.openSubscription <- subscribeSpeaker returned for pubkey=$pubkey" }
             // Re-check after the suspending subscribeSpeaker — the user
             // may have removed this speaker via updateSpeakers / disconnected
             // while the SUBSCRIBE was in flight. If so, abandon the handle
@@ -1004,6 +1007,7 @@ class NestViewModel(
         // First frame for this subscription — clear the buffering
         // overlay. Subsequent frames are no-ops here.
         if (_uiState.value.connectingSpeakers.contains(pubkey)) {
+            Log.d("NestRx") { "VM.onSpeakerActivity FIRST frame for pubkey=$pubkey — clearing spinner" }
             _uiState.update { it.copy(connectingSpeakers = (it.connectingSpeakers - pubkey).toPersistentSet()) }
         }
         if (!_uiState.value.speakingNow.contains(pubkey)) {