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/tasks/03_init.yml

@@ -0,0 +1,15 @@
+- name: "load variables from {{ DOCKER_VARS_FILE }}"
+  include_vars: "{{ DOCKER_VARS_FILE }}"
+
+- name: "create directory {{ KEYCLOAK_REALM_IMPORT_DIR_HOST }}"
+  file:
+    path: "{{ KEYCLOAK_REALM_IMPORT_DIR_HOST }}"
+    state: directory
+    mode: "0755"
+
+- name: "Copy REALM import file '{{ KEYCLOAK_REALM_IMPORT_FILE_SRC }}' to '{{ KEYCLOAK_REALM_IMPORT_FILE_DST }}'"
+  template:
+    src: "{{ KEYCLOAK_REALM_IMPORT_FILE_SRC }}"
+    dest: "{{ KEYCLOAK_REALM_IMPORT_FILE_DST }}"
+    mode: "0770"
+  when: KEYCLOAK_REALM_IMPORT_ENABLED | bool