Container image for pgAdmin 4 (percona-pgadmin4), built from the
ppg:devel:pgadmin RPMs on UBI 9. Bundles the Percona PostgreSQL client
binaries for majors 14-18 so pgAdmin's Backup/Restore and external
Query Tool features work against any supported server version.
Design: docs/superpowers/specs/2026-09-02-pgadmin4-container-design.md