refactor(web-app-mediawiki): unify debug & oidc handling via _ensure_require, introduce host-side prep, switch to bind mounts

- Removed obsolete Installation.md, TODO.md, 02_debug.yml, 05_oidc.yml and legacy debug enable/disable tasks
- Added 01_prep.yml to render debug.php/oidc.php on host side before container start
- Introduced _ensure_require.yml for generic require_once management in LocalSettings.php
- Renamed 01_install.yml -> 02_install.yml to align with new numbering
- Updated docker-compose.yml.j2 to bind-mount mw-local into /opt/mw-local
- Adjusted vars/main.yml to define MEDIAWIKI_LOCAL_MOUNT_DIR and MEDIAWIKI_LOCAL_PATH
- Templates debug.php.j2 and oidc.php.j2 now gated by MODE_DEBUG and MEDIAWIKI_OIDC_ENABLED
- main.yml now orchestrates prep, install, debug, extensions, oidc require, admin consistently

Ref: https://chatgpt.com/share/68b57db2-efcc-800f-a733-aca952298437

roles/web-app-mediawiki/tasks/main.yml

@@ -3,20 +3,35 @@
   include_role: 
     name: sys-stk-full-stateful
   vars:
-    docker_compose_flush_handlers: true
+    docker_compose_flush_handlers: false
+
+- name: "Prepare host files for '{{ application_id }}'"
+  include_tasks: 01_prep.yml
+
+- name: "flush handlers for '{{ application_id }}' after preparation finished"
+  meta: flush_handlers
 
 - name: "Load install procedures for '{{ application_id }}''"
-  include_tasks: 01_install.yml
+  include_tasks: 02_install.yml
 
-- name: "Load debug procedures for '{{ application_id }}''"
-  include_tasks: 02_debug.yml
+
+- name: "DEBUG | Ensure require_once(debug.php) matches MODE_DEBUG"
+  include_tasks: _ensure_require.yml
+  vars:
+    ensure_present: "{{ MODE_DEBUG | bool }}"
+    require_path: "{{ MEDIAWIKI_LOCAL_PATH }}/debug.php"
+  when: MODE_DEBUG | bool
 
 - name: "Load admin setup procedures for '{{ application_id }}''"
   include_tasks: 03_admin.yml
 
-- name: "Load OIDC procedures for '{{ application_id }}''"
-  include_tasks: "{{ item }}"
-  loop:
-    - 04_extensions.yml
-    - 05_oidc.yml
-  when: MEDIAWIKI_OIDC_ENABLED | bool
+- name: "Load extensions procedures for '{{ application_id }}''"
+  include_tasks: "04_extensions.yml"
+  when: MEDIAWIKI_OIDC_ENABLED | bool
+
+- name: "OIDC | Ensure require_once(oidc.php) present"
+  include_tasks: _ensure_require.yml
+  vars:
+    ensure_present: true
+    require_path: "{{ MEDIAWIKI_LOCAL_PATH }}/oidc.php"
+  when: MEDIAWIKI_OIDC_ENABLED | bool