fix(hermes-adapter): kill old bridge process on reconnect to prevent zombie accumulation

When the MemOS bridge fails to initialize (e.g., stuck on orphan recovery
due to external API rate limiting), _reconnect_bridge() would call close()
on the old bridge — which only closes stdin without killing the process.
The old process, stuck in its init loop, never reads stdin EOF and lives
forever. Each failed reconnect cycle spawned new node processes,
accumulating zombies until OOM killer was invoked.

Changes:
- bridge_client.py: add terminate() method (SIGKILL + wait)
- __init__.py: call old_bridge.terminate() during reconnect

Author: futursolar

apps/memos-local-plugin/adapters/hermes/memos_provider/__init__.py

@@ -1641,6 +1641,11 @@ def _reconnect_bridge(self, session_id: str = "", *, timeout: float = 30.0) -> N
         if old_bridge:
             with contextlib.suppress(Exception):
                 old_bridge.close()
+            # Kill the old process to prevent zombie accumulation.
+            # close() alone only closes stdin — headless bridges may
+            # not notice and keep running forever.
+            with contextlib.suppress(Exception):
+                old_bridge.terminate()
         ensure_bridge_running()
         self._bridge = MemosBridgeClient()
         self._bridge.register_host_handler(

apps/memos-local-plugin/adapters/hermes/memos_provider/bridge_client.py

@@ -218,6 +218,18 @@ def register_host_handler(
         """
         self._host_handlers[method] = handler
 
+    def terminate(self) -> None:
+        """Kill the bridge subprocess (SIGKILL). Use when the bridge is
+        stuck/unresponsive and must be forcefully cleaned up before
+        starting a new one."""
+        self._closed = True
+        with contextlib.suppress(Exception):
+            self._proc.stdin.close()
+        with contextlib.suppress(Exception):
+            self._proc.kill()
+        with contextlib.suppress(Exception):
+            self._proc.wait(timeout=5)
+
     def close(self) -> None:
         if self._closed:
             return