mcp-authkit Postgres Token Store

Postgres-backed TokenStore for mcp-authkit, providing durable storage for Personal Access Tokens, refresh tokens, and upstream credential caches. Current stable version is 0.2.1, released as part of the mcp-authkit ecosystem. It wraps node-postgres (pg) and supports PostgreSQL 13+. Key differentiator: pools are consumer-owned, and store.close() does not close the pool to avoid ownership conflicts. Ships TypeScript types and uses ESM-only imports. Release cadence is tied to mcp-authkit releases.