fix: add summary fallback and stabilize recording sink

tests/test_bot.py

@@ -9,6 +9,7 @@ sys.path.insert(0, os.path.dirname(os.path.dirname(__file__)))
 import discord
 
 import bot
+import voice
 
 
 class FakeChannel:
@@ -66,3 +67,42 @@ def test_build_retry_notice_mentions_reason_and_path():
     assert "OpenRouter 502" in message
     assert "meeting.wav" in message
     assert "`/retry`" in message
+
+
+def test_meeting_recorder_wraps_wave_sink_with_silence_generator(tmp_path, monkeypatch):
+    created = {}
+
+    class FakeWaveSink:
+        def __init__(self, output_path):
+            self.output_path = output_path
+            created["wave"] = self
+
+    class FakeSilenceGeneratorSink:
+        def __init__(self, destination):
+            self.destination = destination
+            created["silence"] = self
+
+    class FakeVoiceClient:
+        def __init__(self):
+            self.listened_sink = None
+
+        def is_listening(self):
+            return False
+
+        def listen(self, sink, after):
+            self.listened_sink = sink
+            created["after"] = after
+
+    monkeypatch.setattr(voice.voice_recv, "WaveSink", FakeWaveSink)
+    monkeypatch.setattr(voice.voice_recv, "SilenceGeneratorSink", FakeSilenceGeneratorSink)
+
+    vc = FakeVoiceClient()
+    output_path = tmp_path / "meeting.wav"
+    recorder = voice.MeetingRecorder(vc, str(output_path))
+
+    asyncio.run(recorder.start(lambda error: None))
+
+    assert created["wave"].output_path == str(output_path)
+    assert created["silence"].destination is created["wave"]
+    assert vc.listened_sink is created["silence"]
+    assert recorder.recording is True