chore(admin-ui): introduce list-card component and apply to subscriptions index

tests/Feature/AdminSiteSubscriptionsIndexShouldUseListCardStructureTest.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Tests\Feature;
+
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminSiteSubscriptionsIndexShouldUseListCardStructureTest extends TestCase
+{
+    use RefreshDatabase;
+
+    protected function loginAsPlatformAdmin(): void
+    {
+        $this->seed();
+
+        $this->post('/admin/login', [
+            'email' => 'platform.admin@demo.local',
+            'password' => 'Platform@123456',
+        ])->assertRedirect('/admin');
+    }
+
+    public function test_admin_site_subscriptions_index_should_use_list_card_structure(): void
+    {
+        $this->loginAsPlatformAdmin();
+
+        $response = $this->get('/admin/site-subscriptions');
+        $response->assertOk();
+
+        // 护栏：订阅列表区域应使用统一 List Card 结构，便于全站列表页风格统一。
+        $response->assertSee('list-card', false);
+        $response->assertSee('list-card-header', false);
+        $response->assertSee('list-card-body', false);
+        $response->assertSee('list-card-table', false);
+    }
+}