feat: add raw artifact audit trail

tests/test_import_templates.py

@@ -7,6 +7,7 @@ from pathlib import Path
 
 from shanghai_housing.db import connect, import_template_file
 from shanghai_housing.import_templates import validate_csv_file, validate_import_rows
+from shanghai_housing.raw_artifacts import fingerprint_file
 
 
 class ImportTemplateTests(unittest.TestCase):
@@ -79,6 +80,15 @@ class ImportTemplateTests(unittest.TestCase):
         self.assertEqual(len(rows), 1)
         self.assertEqual(rows[0]["level"], "shanghai")
 
+    def test_fingerprints_import_file_without_local_path(self) -> None:
+        fingerprint = fingerprint_file(Path("docs/import_templates/policy_events.csv"))
+
+        self.assertEqual(fingerprint.original_filename, "policy_events.csv")
+        self.assertEqual(len(fingerprint.sha256), 64)
+        self.assertGreater(fingerprint.size_bytes, 0)
+        self.assertTrue(fingerprint.raw_uri.startswith("raw://sha256/"))
+        self.assertNotIn("/Users/", fingerprint.raw_uri)
+
 
 if __name__ == "__main__":
     unittest.main()