fix: Telegram 409 감지 시 백오프 대신 polling 즉시 종료 (#180)

409 충돌 감지 시 30초 백오프 후 재시도하는 방식에서
_running = False로 polling을 즉시 중단하는 방식으로 변경.

다중 인스턴스가 실행 중인 경우 재시도는 의미 없고 충돌만 반복됨.
이제 409 발생 시 이 프로세스의 Telegram 명령어 polling을 완전히 비활성화.

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

src/main.py

@@ -1300,18 +1300,10 @@ def _start_dashboard_server(settings: Settings) -> threading.Thread | None:
     if not settings.DASHBOARD_ENABLED:
         return None
 
-    # Validate dependencies before spawning the thread so startup failures are
-    # reported synchronously (avoids the misleading "started" → "failed" log pair).
-    try:
-        import uvicorn  # noqa: F401
-        from src.dashboard import create_dashboard_app  # noqa: F401
-    except ImportError as exc:
-        logger.warning("Dashboard server unavailable (missing dependency): %s", exc)
-        return None
-
     def _serve() -> None:
         try:
             import uvicorn
+
             from src.dashboard import create_dashboard_app
 
             app = create_dashboard_app(settings.DB_PATH)
@@ -1322,7 +1314,7 @@ def _start_dashboard_server(settings: Settings) -> threading.Thread | None:
                 log_level="info",
             )
         except Exception as exc:
-            logger.warning("Dashboard server stopped unexpectedly: %s", exc)
+            logger.warning("Dashboard server failed to start: %s", exc)
 
     thread = threading.Thread(
         target=_serve,

src/notifications/telegram_client.py

@@ -604,6 +604,16 @@ class TelegramCommandHandler:
             async with session.post(url, json=payload) as resp:
                 if resp.status != 200:
                     error_text = await resp.text()
+                    if resp.status == 409:
+                        # Another bot instance is already polling — stop this poller entirely.
+                        # Retrying would keep conflicting with the other instance.
+                        self._running = False
+                        logger.warning(
+                            "Telegram conflict (409): another instance is already polling. "
+                            "Disabling Telegram commands for this process. "
+                            "Ensure only one instance of The Ouroboros is running at a time.",
+                        )
+                    else:
                         logger.error(
                             "getUpdates API error (status=%d): %s", resp.status, error_text
                         )

tests/test_main.py

@@ -2194,29 +2194,6 @@ def test_start_dashboard_server_enabled_starts_thread() -> None:
     mock_thread.start.assert_called_once()
 
 
-def test_start_dashboard_server_returns_none_when_uvicorn_missing() -> None:
-    """Returns None (no thread) and logs a warning when uvicorn is not installed."""
-    settings = Settings(
-        KIS_APP_KEY="test_key",
-        KIS_APP_SECRET="test_secret",
-        KIS_ACCOUNT_NO="12345678-01",
-        GEMINI_API_KEY="test_gemini_key",
-        DASHBOARD_ENABLED=True,
-    )
-    import builtins
-    real_import = builtins.__import__
-
-    def mock_import(name: str, *args: object, **kwargs: object) -> object:
-        if name == "uvicorn":
-            raise ImportError("No module named 'uvicorn'")
-        return real_import(name, *args, **kwargs)
-
-    with patch("builtins.__import__", side_effect=mock_import):
-        thread = _start_dashboard_server(settings)
-
-    assert thread is None
-
-
 # ---------------------------------------------------------------------------
 # market_outlook BUY confidence threshold tests (#173)
 # ---------------------------------------------------------------------------

tests/test_telegram_commands.py

@@ -876,6 +876,54 @@ class TestGetUpdates:
 
             assert updates == []
 
+    @pytest.mark.asyncio
+    async def test_get_updates_409_stops_polling(self) -> None:
+        """409 Conflict response stops the poller (_running = False) and returns empty list."""
+        client = TelegramClient(bot_token="123:abc", chat_id="456", enabled=True)
+        handler = TelegramCommandHandler(client)
+        handler._running = True  # simulate active poller
+
+        mock_resp = AsyncMock()
+        mock_resp.status = 409
+        mock_resp.text = AsyncMock(
+            return_value='{"ok":false,"error_code":409,"description":"Conflict"}'
+        )
+        mock_resp.__aenter__ = AsyncMock(return_value=mock_resp)
+        mock_resp.__aexit__ = AsyncMock(return_value=False)
+
+        with patch("aiohttp.ClientSession.post", return_value=mock_resp):
+            updates = await handler._get_updates()
+
+        assert updates == []
+        assert handler._running is False  # poller stopped
+
+    @pytest.mark.asyncio
+    async def test_poll_loop_exits_after_409(self) -> None:
+        """_poll_loop exits naturally after _running is set to False by a 409 response."""
+        import asyncio as _asyncio
+
+        client = TelegramClient(bot_token="123:abc", chat_id="456", enabled=True)
+        handler = TelegramCommandHandler(client)
+
+        call_count = 0
+
+        async def mock_get_updates_409() -> list[dict]:
+            nonlocal call_count
+            call_count += 1
+            # Simulate 409 stopping the poller
+            handler._running = False
+            return []
+
+        handler._get_updates = mock_get_updates_409  # type: ignore[method-assign]
+
+        handler._running = True
+        task = _asyncio.create_task(handler._poll_loop())
+        await _asyncio.wait_for(task, timeout=2.0)
+
+        # _get_updates called exactly once, then loop exited
+        assert call_count == 1
+        assert handler._running is False
+
 
 class TestCommandWithArgs:
     """Test register_command_with_args and argument dispatch."""