Refactor AI daily report pipeline

tests/test_env_loading.py

@@ -0,0 +1,39 @@
+import importlib.util
+import os
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+
+ROOT = Path(__file__).resolve().parents[1]
+SCRIPT = ROOT / "script" / "ai_daily_blog_pipeline.py"
+
+
+def load_pipeline_module():
+    spec = importlib.util.spec_from_file_location("ai_daily_blog_pipeline", SCRIPT)
+    module = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(module)
+    return module
+
+
+class EnvLoadingTests(unittest.TestCase):
+    def test_project_env_is_loaded_and_process_env_wins(self):
+        module = load_pipeline_module()
+        env_text = "LLM_MODEL=file-model\nLLM_BASE_URL=https://file.example/v1\n"
+
+        with patch.object(module.Path, "home", return_value=ROOT / "missing-home"):
+            with patch.dict(os.environ, {"LLM_MODEL": "process-model"}, clear=False):
+                with patch.object(module, "PROJECT_ENV_PATH", ROOT / ".env.test"):
+                    (ROOT / ".env.test").write_text(env_text, encoding="utf-8")
+                    try:
+                        env = module.load_env()
+                    finally:
+                        (ROOT / ".env.test").unlink(missing_ok=True)
+
+        self.assertEqual(env["LLM_BASE_URL"], "https://file.example/v1")
+        self.assertEqual(env["LLM_MODEL"], "process-model")
+
+
+if __name__ == "__main__":
+    unittest.main()
+