fix: agent cleanup on disconnect + targeted audio input

- Agent disconnects custom room when all real participants leave
  (prevents zombie participants blocking auto-dispatch)
- Bot sends m.call.member state event on call detection
  (Element Call shows bot as joined)
- Use RoomInputOptions(participant_identity=...) to target real user
  audio input (framework agent-AJ_xxx participant was confusing RoomIO)
- Removed incorrect bot dispatch (Matrix room ID != LiveKit room name)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

bot.py

@@ -10,6 +10,7 @@ from nio import (
     InviteMemberEvent,
     MegolmEvent,
     SyncResponse,
+    UnknownEvent,
     KeyVerificationStart,
     KeyVerificationCancel,
     KeyVerificationKey,
@@ -18,6 +19,9 @@ from nio import (
 )
 from livekit import api
 
+BOT_DEVICE_ID = "AIBOT"
+CALL_MEMBER_TYPE = "org.matrix.msc3401.call.member"
+
 logger = logging.getLogger("matrix-ai-bot")
 
 HOMESERVER = os.environ["MATRIX_HOMESERVER"]
@@ -47,6 +51,7 @@ class Bot:
         )
         self.lkapi = None
         self.dispatched_rooms = set()
+        self.active_calls = set()  # rooms where we've sent call member event
 
     async def start(self):
         # Restore existing session or create new one
@@ -80,6 +85,7 @@ class Bot:
         self.lkapi = api.LiveKitAPI(LK_URL, LK_KEY, LK_SECRET)
         self.client.add_event_callback(self.on_invite, InviteMemberEvent)
         self.client.add_event_callback(self.on_megolm, MegolmEvent)
+        self.client.add_event_callback(self.on_unknown, UnknownEvent)
         self.client.add_response_callback(self.on_sync, SyncResponse)
         self.client.add_to_device_callback(self.on_key_verification, KeyVerificationStart)
         self.client.add_to_device_callback(self.on_key_verification, KeyVerificationKey)
@@ -115,6 +121,69 @@ class Bot:
                     self.client.verify_device(device)
                     logger.info("Auto-trusted device %s of %s", device.device_id, user_id)
 
+    async def on_unknown(self, room, event: UnknownEvent):
+        """Handle call member state events to join calls."""
+        if event.type != CALL_MEMBER_TYPE:
+            return
+        if event.sender == BOT_USER:
+            return  # ignore our own events
+
+        # Non-empty content means someone started/is in a call
+        if event.source.get("content", {}):
+            room_id = room.room_id
+            if room_id in self.active_calls:
+                return
+
+            logger.info("Call detected in %s from %s, joining...", room_id, event.sender)
+            self.active_calls.add(room_id)
+
+            # Get the foci_preferred from the caller's event
+            content = event.source["content"]
+            foci = content.get("foci_preferred", [{
+                "type": "livekit",
+                "livekit_service_url": f"{HOMESERVER}/livekit-jwt-service",
+                "livekit_alias": room_id,
+            }])
+
+            # Send our own call member state event
+            call_content = {
+                "application": "m.call",
+                "call_id": "",
+                "scope": "m.room",
+                "device_id": BOT_DEVICE_ID,
+                "expires": 7200000,
+                "focus_active": {
+                    "type": "livekit",
+                    "focus_selection": "oldest_membership",
+                },
+                "foci_preferred": foci,
+                "m.call.intent": "audio",
+            }
+
+            state_key = f"_{BOT_USER}_{BOT_DEVICE_ID}_m.call"
+            try:
+                resp = await self.client.room_put_state(
+                    room_id, CALL_MEMBER_TYPE, call_content, state_key=state_key,
+                )
+                logger.info("Sent call member event in %s: %s", room_id, resp)
+            except Exception:
+                logger.exception("Failed to send call member event in %s", room_id)
+
+        else:
+            # Empty content = someone left the call, check if anyone is still calling
+            room_id = room.room_id
+            if room_id in self.active_calls:
+                # Leave the call too
+                self.active_calls.discard(room_id)
+                state_key = f"_{BOT_USER}_{BOT_DEVICE_ID}_m.call"
+                try:
+                    await self.client.room_put_state(
+                        room_id, CALL_MEMBER_TYPE, {}, state_key=state_key,
+                    )
+                    logger.info("Left call in %s", room_id)
+                except Exception:
+                    logger.exception("Failed to leave call in %s", room_id)
+
     async def on_megolm(self, room, event: MegolmEvent):
         """Log undecryptable messages."""
         logger.warning(