Refactor DB initialization handling: externalize database_init flag for svc-db-mariadb and svc-db-postgres, remove internal auto-detection, and pass explicit init signal from sys-stk-back-stateful. Improves clarity, avoids incorrect credential lookups, and stabilizes central DB setup.

Reference: ChatGPT conversation https://chatgpt.com/share/692def1c-a79c-800f-b7dd-35e1845424bf

roles/svc-db-postgres/defaults/main.yml

@@ -1 +1,2 @@
-postgres_gis_enabled: false # Needed by mobilizon
+postgres_gis_enabled: false # Needed by mobilizon
+database_init:        false # When true a database is initialized

roles/svc-db-postgres/tasks/main.yml

@@ -11,4 +11,4 @@
 
 - name: "Initialize database for '{{ database_name }}'"
   include_tasks: 02_init.yml
-  when: POSTGRES_INIT | bool
+  when: database_init | bool

roles/svc-db-postgres/vars/main.yml

@@ -18,7 +18,6 @@ POSTGRES_NETWORK_NAME:                    "{{ applications | get_app_conf(applic
 POSTGRES_SUBNET:                          "{{ networks.local['svc-db-postgres'].subnet }}"
 POSTGRES_PASSWORD:                        "{{ applications | get_app_conf(application_id, 'credentials.POSTGRES_PASSWORD') }}"
 POSTGRES_PORT:                            "{{ database_port | default(ports.localhost.database[ application_id ]) }}"
-POSTGRES_INIT:                            "{{ database_username is defined and database_password is defined and database_name is defined }}"
 POSTGRES_EXPOSE_LOCAL:                    True # Exposes the db to localhost, almost everytime neccessary
 POSTGRES_CUSTOM_IMAGE_NAME:               "postgres_custom"
 POSTGRES_LOCAL_HOST:                      "127.0.0.1"