feat: 前端适配后端新接口

适配后端统一模型 ID、协议字段、UUID 自动生成和结构化错误响应：

- 类型定义：Provider 新增 protocol 字段，Model 新增 unifiedId，CreateModelInput 移除 id
- API 客户端：提取结构化错误响应中的错误码
- 供应商管理：添加协议选择下拉框和表格列
- 模型管理：移除 ID 输入，显示统一模型 ID（只读）
- Hooks：错误码映射为友好中文消息
- 测试：所有组件测试通过，mock 数据适配新字段
- 文档：更新 README 说明协议字段和统一模型 ID

frontend/src/__tests__/components/ProviderTable.test.tsx

@@ -5,8 +5,8 @@ import { ProviderTable } from '@/pages/Providers/ProviderTable';
 import type { Provider } from '@/types';
 
 const mockModelsData = [
-  { id: 'model-1', providerId: 'openai', modelName: 'gpt-4o', enabled: true },
-  { id: 'model-2', providerId: 'openai', modelName: 'gpt-3.5-turbo', enabled: false },
+  { id: 'model-1', providerId: 'openai', modelName: 'gpt-4o', enabled: true, unifiedId: 'openai/gpt-4o' },
+  { id: 'model-2', providerId: 'openai', modelName: 'gpt-3.5-turbo', enabled: false, unifiedId: 'openai/gpt-3.5-turbo' },
 ];
 
 vi.mock('@/hooks/useModels', () => ({
@@ -20,6 +20,7 @@ const mockProviders: Provider[] = [
     name: 'OpenAI',
     apiKey: 'sk-abcdefgh12345678',
     baseUrl: 'https://api.openai.com/v1',
+    protocol: 'openai',
     enabled: true,
     createdAt: '2024-01-01T00:00:00Z',
     updatedAt: '2024-01-01T00:00:00Z',
@@ -29,6 +30,7 @@ const mockProviders: Provider[] = [
     name: 'Anthropic',
     apiKey: 'sk-ant-test',
     baseUrl: 'https://api.anthropic.com',
+    protocol: 'anthropic',
     enabled: false,
     createdAt: '2024-01-02T00:00:00Z',
     updatedAt: '2024-01-02T00:00:00Z',
@@ -51,11 +53,12 @@ describe('ProviderTable', () => {
 
     expect(screen.getByText('供应商列表')).toBeInTheDocument();
 
-    expect(screen.getByText('OpenAI')).toBeInTheDocument();
+    // Check that provider names appear (they will appear in both name column and potentially protocol column)
+    expect(screen.getAllByText('OpenAI').length).toBeGreaterThan(0);
     expect(screen.getByText('https://api.openai.com/v1')).toBeInTheDocument();
     expect(screen.getByText('****5678')).toBeInTheDocument();
 
-    expect(screen.getByText('Anthropic')).toBeInTheDocument();
+    expect(screen.getAllByText('Anthropic').length).toBeGreaterThan(0);
     expect(screen.getByText('https://api.anthropic.com')).toBeInTheDocument();
     expect(screen.getByText('****test')).toBeInTheDocument();
 
@@ -163,4 +166,36 @@ describe('ProviderTable', () => {
     render(<ProviderTable {...defaultProps} providers={[]} />);
     expect(screen.getByText('暂无供应商，点击上方按钮添加')).toBeInTheDocument();
   });
+
+  it('renders protocol column with correct tags', () => {
+    const { container } = render(<ProviderTable {...defaultProps} />);
+
+    // Check that protocol tags are displayed in the table
+    const protocolCells = container.querySelectorAll('[data-colkey="protocol"]');
+    expect(protocolCells.length).toBeGreaterThan(0);
+
+    // Verify protocol tags exist
+    const tags = container.querySelectorAll('.t-tag');
+    expect(tags.length).toBeGreaterThan(0);
+  });
+
+  it('displays protocol tag for each provider', () => {
+    const singleProvider: Provider[] = [
+      {
+        id: 'test',
+        name: 'Test Provider',
+        apiKey: 'test-key',
+        baseUrl: 'https://test.com',
+        protocol: 'openai',
+        enabled: true,
+        createdAt: '2024-01-01T00:00:00Z',
+        updatedAt: '2024-01-01T00:00:00Z',
+      },
+    ];
+    const { container } = render(<ProviderTable {...defaultProps} providers={singleProvider} />);
+
+    // Should display protocol column
+    const protocolCell = container.querySelector('[data-colkey="protocol"]');
+    expect(protocolCell).toBeInTheDocument();
+  });
 });