chore(admin-ui): stop loading legacy admin.css and enforce new css stack

tests/Feature/AdminLoginPageShouldLoadNewAdminCssStackTest.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace Tests\Feature;
+
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Tests\TestCase;
+
+class AdminLoginPageShouldLoadNewAdminCssStackTest extends TestCase
+{
+    use RefreshDatabase;
+
+    public function test_admin_login_page_should_load_new_admin_css_stack(): void
+    {
+        $response = $this->get('/admin/login');
+        $response->assertOk();
+
+        // login 页面也要走 token 化样式栈，避免被 legacy admin.css 暗色风格污染。
+        $response->assertDontSee('/css/admin.css', false);
+        $response->assertSee('/css/admin-theme.css', false);
+        $response->assertSee('/css/admin-base.css', false);
+        $response->assertSee('/css/admin-components.css', false);
+    }
+}