fix(backends,conversations,telegram,ui): a background subagent reports back as its own turn

src/beaver_gateway/conversations/state.py

@@ -127,6 +127,12 @@ class State:
         self._tasks = set()
         self._idle_task = None
         self.scheduler = None
+        for backend in backends.values():
+            if hasattr(backend, "waker"):
+                backend.waker = self._woken
+
+    async def _woken(self, key: str, note: str) -> None:
+        raise NotImplementedError
 
     @property
     def db(self) -> Database: