fix(agent): proxy gradio config and reduce translate blocking

backend/tests/plugins/translate/test_batch_proc.py

@@ -83,16 +83,37 @@ class TestCreateBatch:
 class TestDetectLanguages:
     """Verify _detect_languages."""
 
-    def test_detects_languages(self, db_session):
+    @pytest.mark.asyncio
+    async def test_detects_languages(self, db_session):
         config = MagicMock()
         svc = BatchProcessingService(db_session, config)
         rows = _batch_rows(2)
         with patch('src.plugins.translate._batch_proc.batch_detect',
                    return_value=["en", "fr"]):
-            svc._detect_languages(rows, ["fr", "de"])
+            await svc._detect_languages(rows, ["fr", "de"])
             assert rows[0]["_detected_lang"] == "en"
             assert rows[1]["_detected_lang"] == "fr"
 
+    @pytest.mark.asyncio
+    async def test_detect_languages_offloads_to_thread(self, db_session):
+        """Regression: CPU-bound lingua batch detection must not run on event loop."""
+        config = MagicMock()
+        svc = BatchProcessingService(db_session, config)
+        rows = _batch_rows(2)
+
+        async def fake_to_thread(fn, texts, target_languages):
+            assert fn.__name__ == "batch_detect"
+            assert texts == ["Hello world 0", "Hello world 1"]
+            assert target_languages == ["fr"]
+            return ["en", "en"]
+
+        with patch('src.plugins.translate._batch_proc.asyncio.to_thread',
+                   new=AsyncMock(side_effect=fake_to_thread)) as mock_to_thread:
+            await svc._detect_languages(rows, ["fr"])
+
+        mock_to_thread.assert_awaited_once()
+        assert [row["_detected_lang"] for row in rows] == ["en", "en"]
+
 
 class TestCheckCache:
     """Verify _check_cache."""