XWiki: LDAP/OIDC admin mapping, config mounts, and REST installs

- LDAP: move settings to xwiki.cfg; enable trylocal (1/0), group_mapping to XWiki.XWikiAdminGroup,
  and mode_group_sync=always.
- OIDC: add groups claim request (oidc.userinfoclaims), map provider group to XWiki.XWikiAdminGroup,
  and use space-separated scopes.
- Compose: mount xwiki.cfg and xwiki.properties into /usr/local/xwiki.
- Extensions: wait for REST readiness; pre-check OIDC/LDAP extensions (URL-encoded IDs);
  install via REST job only if missing.
- Vars: strict mappings to LDAP.* and OIDC.* (no defaults), add XWIKI_ADMIN_GROUP and derived DNs.
- Config: expose ldap.local_enabled; tidy meta tags; README grammar update.

Conversation: https://chatgpt.com/share/68c2b8ad-4814-800f-b377-065f967998db

roles/web-app-xwiki/meta/main.yml

@@ -8,7 +8,10 @@ galaxy_info:
     Kevin Veen-Birkenbach
     Consulting & Coaching Solutions
     https://www.veen.world
-  galaxy_tags: [wiki, collaboration, knowledge, documentation, cms]
+  galaxy_tags:
+    - wiki
+    - documentation
+    - xwiki
   repository: "https://s.infinito.nexus/code"
   issue_tracker_url: "https://s.infinito.nexus/issues"
   documentation: "https://s.infinito.nexus/code/"