Fix Windows scheduled startup failures

tests/test_service_startup.py

@@ -0,0 +1,28 @@
+import os
+import unittest
+from unittest.mock import patch
+
+from docutranslate import app
+
+
+class ServiceStartupTest(unittest.TestCase):
+    @patch.dict(os.environ, {"DOCUTRANSLATE_STRICT_PORT": "1"}, clear=False)
+    @patch.object(app, "find_free_port", return_value=8011)
+    def test_strict_port_rejects_occupied_configured_port(self, _find_free_port):
+        with self.assertRaisesRegex(RuntimeError, "端口 8010 已被占用"):
+            app.run_app(host="127.0.0.1", port=8010)
+
+    @patch.dict(os.environ, {"DOCUTRANSLATE_STRICT_PORT": ""}, clear=False)
+    @patch.object(app.uvicorn, "run")
+    @patch.object(app, "find_free_port", return_value=8011)
+    def test_interactive_mode_can_still_fall_back_to_free_port(
+        self, _find_free_port, uvicorn_run
+    ):
+        app.run_app(host="127.0.0.1", port=8010)
+        uvicorn_run.assert_called_once_with(
+            app.app, host="127.0.0.1", port=8011, workers=1
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()