feat(admin): 客服中心工单骨架（模型/迁移/路由/菜单/页面）

app/Http/Controllers/Admin/SupportTicketController.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace App\Http\Controllers\Admin;
+
+use App\Http\Controllers\Concerns\ResolvesPlatformAdminContext;
+use App\Http\Controllers\Controller;
+use Illuminate\Http\Request;
+use Illuminate\View\View;
+
+class SupportTicketController extends Controller
+{
+    use ResolvesPlatformAdminContext;
+
+    public function index(Request $request): View
+    {
+        $this->ensurePlatformAdmin($request);
+
+        // 当前阶段：先做最小骨架页，后续再接入列表/筛选/创建/指派/SLA/升级。
+        return view('admin.support_tickets.index');
+    }
+}