Fix/统一修复modal样式失效 (#122)

之前遇到几次弹窗的样式不生效,bug 现在在画布agent的删除对话弹窗又出现了,
这个pr把类似的修改集中到最下层的UnifiedModal,适用于所有的modal,
一些特殊的modal有特殊处理.

画布agent的删除对话弹窗
![shotmd-1785399342.jpg](/attachments/d63d7dc6-bf7e-4f13-bfe8-bc4716cd798f)

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Co-authored-by: 段舒康 <kdletters@qq.com>
Reviewed-on: http://192.168.35.82/git/GenarrativeAI/Genarrative/pulls/122
Reviewed-by: 段舒康 <kdletters@qq.com>
Co-authored-by: 王德宇 <kvtodev@outlook.com>
Co-committed-by: 王德宇 <kvtodev@outlook.com>

src/components/common/PlatformUtilityInfoModal.test.tsx

@@ -1,10 +1,14 @@
 /* @vitest-environment jsdom */
 
 import { render, screen, within } from '@testing-library/react';
-import { expect, test } from 'vitest';
+import { expect, test, vi } from 'vitest';
 
 import { PlatformUtilityInfoModal } from './PlatformUtilityInfoModal';
 
+vi.mock('../auth/AuthUiContext', () => ({
+  useAuthUi: () => ({ platformTheme: 'dark' }),
+}));
+
 test('renders platform utility info modal shell with default platform styling', () => {
   render(
     <PlatformUtilityInfoModal
@@ -19,7 +23,7 @@ test('renders platform utility info modal shell with default platform styling',
   );
 
   const dialog = screen.getByRole('dialog', { name: '工具信息' });
-  expect(dialog.parentElement?.className).toContain('platform-theme--light');
+  expect(dialog.parentElement?.className).toContain('platform-theme--dark');
   expect(dialog.parentElement?.className).toContain('!items-center');
   expect(dialog.className).toContain('platform-remap-surface');
   expect(dialog.className).toContain('rounded-[1.5rem]');