Fix RBAC groups handling and refactor Keycloak role

- Fixed incorrect handling of RBAC group configuration (moved from OIDC claims into dedicated RBAC variable set).
- Unified RBAC group usage across applications (LAM, pgAdmin, phpLDAPadmin, phpMyAdmin, YOURLS).
- Replaced old 'KEYCLOAK_OIDC_RBAC_SCOPE_NAME' with dedicated 'KEYCLOAK_RBAC_GROUP_*' variables.
- Updated OAuth2 Proxy configuration to use 'RBAC.GROUP.CLAIM'.
- Refactored Keycloak role task structure:
  * Renamed and reorganized task files for clarity ('_update.yml', '02_cleanup.yml', etc.).
  * Introduced meta and dependency handling separation.
- Cleaned up Keycloak config defaults and recaptcha placeholders.

roles/web-app-keycloak/templates/import/realm.json.j2

@@ -1430,7 +1430,7 @@
     "phone",
     "microprofile-jwt",
     "organization",
-    "{{ KEYCLOAK_OIDC_RBAC_SCOPE_NAME }}",
+    "{{ KEYCLOAK_RBAC_GROUP_CLAIME }}",
     "{{ applications | get_app_conf(application_id, 'scopes.nextcloud', True) }}"
   ],
   "browserSecurityHeaders": {