The realm_access claim in JWT is a JSON object, not a simple string.
Previous string contains check was looking for escaped quotes in wrong format.
- Parse realm_access as JSON to extract roles array
- Check if 'admin' exists in roles array
- Fallback to string contains check if JSON parsing fails
- Applied fix in RequireGlobalAdmin policy, TenantValidationMiddleware,
and ClubRoleClaimsTransformation
Fixes: Admin users getting 401 when trying to create clubs