Complete overhaul from single-admin to multi-role multi-org system:

- Auth: multi-user login from admin_users table with 9 roles
  (superadmin, admin, moderator, org_admin, org_manager,
  tournament_organizer, sponsor, charity, viewer)
- Permissions: granular permission matrix with org-scoping
- RuleEngine: event-driven workflow automation
- Users module: full CRUD for admin user management
- Workflows module: approval queue, automation rules, org requests
- Dashboard: role-aware with scoped data per role
- Sidebar: permission-filtered navigation per role
- Topbar: shows role badge next to username
- Login: supports all user types
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>