[FEAT] 優化部署流程：加入 RoleSeeder 與 AdminUserSeeder，並實作權限系統基礎架構與多租戶隔離機制

database/seeders/RoleSeeder.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Database\Seeders;
+
+use Illuminate\Database\Seeder;
+use Spatie\Permission\Models\Role;
+use Spatie\Permission\Models\Permission;
+use Illuminate\Support\Facades\Schema;
+
+class RoleSeeder extends Seeder
+{
+    /**
+     * Run the database seeds.
+     */
+    public function run(): void
+    {
+        // 重設快取
+        app()[\Spatie\Permission\PermissionRegistrar::class]->forgetCachedPermissions();
+
+        // 建立角色
+        Role::updateOrCreate(
+            ['name' => 'super-admin'],
+            ['is_system' => true]
+        );
+
+        Role::updateOrCreate(
+            ['name' => 'tenant-admin'],
+            ['is_system' => true]
+        );
+    }
+}