sys-svc-rdbms: Refactor database service templates and add version support for Magento

- Unified Jinja2 variable spacing in tasks and templates
- Introduced database_image and database_version variables in vars/database.yml
- Updated mariadb.yml.j2 and postgres.yml.j2 to use {{ database_image }}:{{ database_version }}
- Ensured env file paths and includes are consistent
- Prepared support for versioned database images (needed for Magento deployment)

Ref: https://chatgpt.com/share/68b96a9d-c100-800f-856f-cd23d1eda2ed

roles/sys-svc-rdbms/templates/services/postgres.yml.j2

@@ -2,13 +2,13 @@
 
 {% if not applications | get_app_conf(application_id, 'features.central_database', False) %}  
   {{ database_host }}:
-    image: postgres:{{ applications['svc-db-postgres'].version}}-alpine
+    image: {{ database_image }}:{{ database_version }}
     container_name: {{ application_id | get_entity_name }}-database
     env_file:
-      - {{database_env}}
+      - {{ database_env }}
     restart: {{ DOCKER_RESTART_POLICY }}
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U {{ database_name }}"]
+      test: ["CMD-SHELL", "pg_isready -U {{ database_user }}"]
       interval: 10s
       timeout: 5s
       retries: 6