Phase 2 of the pgbouncer + pgAdmin rollout. pgAdmin4 runs as a Coolify-
managed container on the same Docker network as pgbouncer, with a
pre-registered server entry so the tracksolid_db (via pgbouncer) tree
appears immediately on first login.
Net effect: admin tooling moves on-VM (low latency, persistent workspace
in pgadmin-data volume) and connects through pgbouncer:6432 in transaction
mode, so opening many Query Tool tabs no longer exhausts max_connections.
The desktop pgAdmin can be retired once this is verified live, after
which host port 5433 can also be closed.
Requires PGADMIN_DEFAULT_EMAIL and PGADMIN_DEFAULT_PASSWORD in the
Coolify env, plus a subdomain mapping to this service on port 80.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>