守住 RAG embedding signature migration

tests/test_migration_metadata_coverage.py

@@ -65,6 +65,22 @@ def test_host_health_probe_label_check_accepts_runtime_labels():
         assert f"'{label}'" in migration
 
 
+def test_rag_embedding_signature_migration_covers_query_and_learning_tables():
+    migration = (ROOT / "migrations" / "034_add_embedding_signature_to_rag_tables.sql").read_text(encoding="utf-8")
+
+    expected_snippets = [
+        "ALTER TABLE IF EXISTS rag_query_log",
+        "ADD COLUMN IF NOT EXISTS embedding_signature VARCHAR(64)",
+        "idx_rag_query_log_embedding_signature",
+        "WHERE query_embedding IS NOT NULL AND embedding_signature IS NOT NULL",
+        "ALTER TABLE IF EXISTS learning_episodes",
+        "idx_le_embedding_signature",
+        "WHERE embedding IS NOT NULL AND embedding_signature IS NOT NULL",
+    ]
+    for snippet in expected_snippets:
+        assert snippet in migration
+
+
 def test_legacy_zero_byte_database_decoys_do_not_return():
     for filename in ["momo.db", "momo_data.db", "momo_database.db"]:
         assert not (ROOT / "database" / filename).exists()