web-app-xwiki: add SuperAdmin bootstrap support

- Added schema entry for superadminpassword
- Added vars for XWIKI_SUPERADMIN_USERNAME/PASSWORD
- Extended xwiki.properties.j2 to configure superadminpassword
- Added 02_bootstrap_admin.yml to create XWiki admin via REST using SuperAdmin
- Updated REST URLs to use XWIKI_REST_GENERAL
- Enabled CSP flag unsafe-inline

Conversation: https://chatgpt.com/share/68c39ddb-e9cc-800f-b32f-9d4c1e09e43e

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

@@ -25,7 +25,9 @@ features:
 server:
   csp:
     whitelist:      {}
-    flags:          {}
+    flags:
+      script-src-elem:
+        unsafe-inline:  true
   domains:
     canonical:
       - "x.wiki.{{ PRIMARY_DOMAIN }}"