✨ feat(ai): 接入 CodeBuddy CLI 并兼容官方登录态

- 新增 CodeBuddy CLI provider，支持 codebuddy/cbc 命令调用与输出解析
- 将 Base URL、API Key/Auth Token、自定义请求头映射到 CodeBuddy CLI 环境变量
- 扩展 custom provider 路由与测试链路，兼容空 Base URL 和 CLI 默认模型选择
- AI 设置新增 CodeBuddy 预设，并补齐 preset 回显识别与匹配逻辑
- 修正就绪态、模型列表与表单校验，允许留空凭证直接复用本机已登录账号
- 补充前后端定向测试并覆盖 CodeBuddy 配置展示文案

Close #574

frontend/src/utils/aiProviderPresets.test.ts

@@ -29,6 +29,7 @@ const PRESETS: PresetMatcher[] = [
     defaultBaseUrl: QWEN_CODING_PLAN_ANTHROPIC_BASE_URL,
     fixedApiFormat: 'claude-cli',
   },
+  { key: 'codebuddy', backendType: 'custom', defaultBaseUrl: '', fixedApiFormat: 'codebuddy-cli' },
   { key: 'custom', backendType: 'custom', defaultBaseUrl: '' },
 ];
 
@@ -112,7 +113,7 @@ describe('ai provider preset helpers', () => {
 
   it('keeps the user-entered base URL for custom-like presets', () => {
     expect(resolvePresetBaseURL({
-      presetKey: 'custom',
+      presetKey: 'codebuddy',
       presetDefaultBaseUrl: '',
       valuesBaseUrl: 'https://example-proxy.internal/v1',
     })).toBe('https://example-proxy.internal/v1');
@@ -182,4 +183,18 @@ describe('resolveProviderPresetKey', () => {
 
     expect(key).toBe('qwen-bailian');
   });
+
+  it('能识别没有 Base URL 的 CodeBuddy CLI 预设', () => {
+    const key = resolveProviderPresetKey(
+      {
+        type: 'custom',
+        apiFormat: 'codebuddy-cli',
+        baseUrl: '',
+      },
+      PRESETS,
+      'custom',
+    );
+
+    expect(key).toBe('codebuddy');
+  });
 });

frontend/src/utils/aiProviderPresets.ts

@@ -17,7 +17,7 @@ export const QWEN_CODING_PLAN_MODELS = [
   'glm-4.7',
 ];
 
-const CUSTOM_LIKE_PRESET_KEYS = new Set(['custom', 'ollama']);
+const CUSTOM_LIKE_PRESET_KEYS = new Set(['custom', 'ollama', 'codebuddy']);
 
 export interface ResolvePresetModelSelectionInput {
   presetKey: string;
@@ -126,6 +126,17 @@ export const resolveProviderPresetKey = (
   }
 
   const fingerprint = getProviderFingerprint(provider.baseUrl);
+  const formatOnlyPreset = presets.find((preset) =>
+    preset.backendType === provider.type
+    && Boolean(preset.fixedApiFormat)
+    && preset.fixedApiFormat === provider.apiFormat
+    && getProviderFingerprint(preset.defaultBaseUrl) === ''
+    && fingerprint === '',
+  );
+  if (formatOnlyPreset) {
+    return formatOnlyPreset.key;
+  }
+
   const exactPreset = presets.find((preset) =>
     preset.backendType === provider.type
     && fingerprint !== ''