- Adds pg dependency for direct PostgreSQL connections to tenant DBs
- TenantConnectionManager: singleton managing Map<tenantId, Pool>
- provisionDatabase: creates new DB with tables and indexes
- deprovisionDatabase: soft-deletes by renaming DB
- Automatic idle pool cleanup every 60s (5min threshold)
- Max 3 connections per pool (6/tenant with 2 PM2 workers)
- Graceful shutdown support for all pools
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>