fix: 校验独立站公开快照并补充自托管说明

tests/test_verify_public_snapshot.py

@@ -0,0 +1,31 @@
+import json
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+from scripts.verify_public_snapshot import check_url
+
+
+class VerifyPublicSnapshotTests(unittest.TestCase):
+    def test_public_snapshot_must_match_generated_at_and_as_of_date(self):
+        with tempfile.TemporaryDirectory() as tmp:
+            path = Path(tmp) / "textile-intelligence.json"
+            path.write_text(json.dumps({"generated_at": "2026-08-17T12:30:21Z", "as_of_date": "2026-08-17"}), encoding="utf-8")
+
+            class Response:
+                def __enter__(self):
+                    return self
+
+                def __exit__(self, *args):
+                    return False
+
+                def read(self):
+                    return b'{"generated_at":"2026-08-17T12:30:21Z","as_of_date":"2026-08-17"}'
+
+            with patch("scripts.verify_public_snapshot.urlopen", return_value=Response()):
+                self.assertEqual(check_url("https://example.test", "/data/textile-intelligence.json", path), ("2026-08-17T12:30:21Z", "2026-08-17"))
+
+
+if __name__ == "__main__":
+    unittest.main()