feat(api): Postgres persistence for registries + scans (owner-scoped, fail-closed)

- schema migration 001 (registries, scans; owner_sub = introspected subject)
- pg pool + services; scan ownership enforced in SQL (INSERT ... SELECT WHERE owner_sub)
- real handlers: 201/400/404/500, owner-scoped GET/POST, listScans registryId filter
- graceful shutdown closes pool; 7 new persistence tests (21/21)

apps/api/package.json

@@ -11,14 +11,16 @@
     "test": "vitest run"
   },
   "dependencies": {
-    "@siax/c0py-core": "workspace:*",
     "@siax/c0py-config": "workspace:*",
+    "@siax/c0py-core": "workspace:*",
     "@siax/c0py-types": "workspace:*",
     "fastify": "^5.12.0",
+    "pg": "^8.23.0",
     "zod": "^3.24.0"
   },
   "devDependencies": {
     "@types/node": "^24.0.0",
+    "@types/pg": "^8.23.1",
     "tsx": "^4.21.0",
     "typescript": "^5.7.2",
     "vitest": "^3.0.0"