Fix governed runtime model registration

backend/tests/test_runtime_model_provenance_migration.py

@@ -135,3 +135,31 @@ def test_generated_sidecar_passes_exact_runtime_contract(tmp_path: Path) -> None
     assert validated.model_sha256 == evidence["checksums"]["model"]
     assert validated.runtime_manifest_sha256 == payload["metadata"]["runtime_manifest_sha256"]
     assert module._write_manifest_atomically(manifest_path, payload) is False
+
+
+def test_model_registry_definition_is_runtime_ready_without_mutating_server_owned_row() -> None:
+    from app.services.source_registry_service import SourceRegistryService
+
+    definition = SourceRegistryService.definition_for("model")
+
+    assert definition.ingest_status == "configured"
+    assert definition.freshness_status == "current"
+    script = SCRIPT.read_text(encoding="utf-8")
+    assert 'source.ingest_status = "configured"' not in script
+    assert 'source.freshness_status = "current"' not in script
+
+
+def test_model_registry_status_migration_is_narrow_and_restores_write_guard() -> None:
+    migration = (
+        ROOT
+        / "backend"
+        / "alembic"
+        / "versions"
+        / "202608230001_configure_model_source_registry.py"
+    ).read_text(encoding="utf-8")
+
+    assert "WHERE source_key = 'model'" in migration
+    assert "registry_owner' = 'server'" in migration
+    assert migration.count("DISABLE TRIGGER trg_source_registry_write_guard") == 1
+    assert migration.count("ENABLE TRIGGER trg_source_registry_write_guard") == 1
+    assert 'down_revision = "202608010001"' in migration