debug(e2ee): poll frame_cryptors() every 30s for state diagnosis

voice.py

@@ -339,8 +339,19 @@ class VoiceSession:
             except asyncio.TimeoutError:
                 logger.error("Greeting timed out")
 
+            # Periodic E2EE state poll to diagnose incoming decryption
+            _poll_count = 0
             while True:
-                await asyncio.sleep(1)
+                await asyncio.sleep(5)
+                _poll_count += 1
+                if _poll_count % 6 == 0:  # Every 30s
+                    try:
+                        cryptors = self.lk_room.e2ee_manager.frame_cryptors()
+                        for c in cryptors:
+                            logger.info("E2EE_CRYPTOR: identity=%s key_index=%d enabled=%s",
+                                        c.participant_identity, c.key_index, c.enabled)
+                    except Exception as e:
+                        logger.debug("frame_cryptors() failed: %s", e)
 
         except asyncio.CancelledError:
             logger.info("Session cancelled for %s", self.room_id)