Remove the dedicated stack-postgres service and postgres_data volume.
Instead join the openbrain_brain-internal overlay network and connect
to openbrain_brain-db for all database operations.
- Add mosaic-db-init service to provision mosaic user/db in openbrain's postgres
- Update synapse-db-init to use BRAIN_DB_ADMIN_* credentials and openbrain_brain-db host
- Update api DATABASE_URL to openbrain_brain-db:5432
- Add openbrain-brain-internal as external network
Required new Portainer env vars:
BRAIN_DB_ADMIN_USER (default: openbrain)
BRAIN_DB_ADMIN_PASSWORD (openbrain stack's POSTGRES_PASSWORD)
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
