feat: two-role system — super_admin & admin program (Fasa 12)

- Replace is_admin boolean with role enum('super_admin','admin') via migration
- ProgramPolicy: admin program can only view/edit/delete own programs
- EnsureIsAdmin: accepts both roles; EnsureSuperAdmin: super_admin only
- UserController + views: super_admin can manage admin accounts
- Sidebar: user management link & role badge gated on isSuperAdmin()
- Fix Controller base class: add AuthorizesRequests trait
- Fix tests: replace nonAdmin() (invalid enum) with adminProgram() against super_admin-only route

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bootstrap/app.php

@@ -12,7 +12,8 @@ return Application::configure(basePath: dirname(__DIR__))
     )
     ->withMiddleware(function (Middleware $middleware): void {
         $middleware->alias([
-            'admin' => \App\Http\Middleware\EnsureIsAdmin::class,
+            'admin'       => \App\Http\Middleware\EnsureIsAdmin::class,
+            'super_admin' => \App\Http\Middleware\EnsureSuperAdmin::class,
         ]);
     })
     ->withExceptions(function (Exceptions $exceptions): void {