Add Phase 1 Identity & Access module (roles, tokens, panel auth, policies)

Implements T1.1-T1.4: Spatie role/permission seeding, Sanctum token
issuance for customer channels and the FastAPI agent (with an
ability-exact-match middleware to tell them apart), Filament admin
panel access restricted to admin-tier roles with the navigation group
order, and skeleton BookingPolicy/RoutePolicy gated on the seeded
permissions ahead of their models landing in later phases.

bootstrap/app.php

@@ -3,6 +3,7 @@
 use Illuminate\Foundation\Application;
 use Illuminate\Foundation\Configuration\Exceptions;
 use Illuminate\Foundation\Configuration\Middleware;
+use Modules\Identity\Http\Middleware\EnsureFastApiAgent;
 
 return Application::configure(basePath: dirname(__DIR__))
     ->withRouting(
@@ -12,7 +13,9 @@ return Application::configure(basePath: dirname(__DIR__))
         health: '/up',
     )
     ->withMiddleware(function (Middleware $middleware): void {
-        //
+        $middleware->alias([
+            'fastapi.agent' => EnsureFastApiAgent::class,
+        ]);
     })
     ->withExceptions(function (Exceptions $exceptions): void {
         //