test(arch): add architecture test suite for Shared layer

tests/Architecture/SharedTest.php

@@ -0,0 +1,65 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Architecture;
+
+describe('Shared Architecture Rules', function (): void {
+    arch('Shared layer does not depend on Domain, Application, Presentation, Infra, or App')
+        ->expect('Shared')
+        ->not->toUse([
+            'Domain',
+            'Application',
+            'Presentation',
+            'Infra',
+            'Infrastructure',
+            'App',
+        ]);
+
+    arch('Shared layer does not depend on Illuminate or Symfony frameworks')
+        ->expect('Shared')
+        ->not->toUse([
+            'Illuminate',
+            'Symfony',
+        ]);
+
+    arch('Shared layer does not use Laravel helper functions')
+        ->expect('Shared')
+        ->not->toUse([
+            'abort',
+            'app',
+            'auth',
+            'asset',
+            'back',
+            'bcrypt',
+            'broadcast',
+            'cache',
+            'config',
+            'cookie',
+            'csrf_token',
+            'dd',
+            'dump',
+            'decrypt',
+            'dispatch',
+            'event',
+            'factory',
+            'logger',
+            'redirect',
+            'request',
+            'response',
+            'route',
+            'session',
+            'storage',
+            'url',
+            'throw_if',
+            'throw_unless',
+            '__',
+            'trans',
+            'trans_choice',
+            'view',
+        ]);
+
+    arch('Shared layer uses strict types')
+        ->expect('Shared')
+        ->toUseStrictTypes();
+});