- Created a new Dockerfile for PostgreSQL using the Bitnami repmgr image.
- Added a comprehensive `librepmgr.sh` script to manage PostgreSQL replication, including functions for node identification, password management, configuration validation, and primary/standby node operations.
- Implemented environment variable validations and PostgreSQL configuration injections for replication settings.
- Included functions for creating the repmgr user and database, as well as handling node registration and failover processes.
Signed-off-by: zhenyus <zhenyus@mathmast.com>
