GitLab

- 新增分组列：展示用户的专属/公开分组，支持 hover 查看详情
- 新增分组筛选：下拉选择或模糊搜索分组名过滤用户
- 专属分组替换：点击专属分组弹出操作菜单，选择目标分组后
  自动授予新分组权限、迁移绑定的 Key、移除旧分组权限
- 后端新增 POST /admin/users/:id/replace-group 端点，事务内
  完成分组替换并失效认证缓存

Add a dedicated modal in group management for viewing, adding, editing,
and deleting per-user rate multipliers within a group.

Backend:
- GET /admin/groups/:id/rate-multipliers - list entries with user details
- PUT /admin/groups/:id/rate-multipliers - batch sync (full replace)
- DELETE /admin/groups/:id/rate-multipliers - clear all entries
- Repository: GetByGroupID, SyncGroupRateMultipliers methods on
  user_group_rate_multipliers table (same table as user-side rates)

Frontend:
- New GroupRateMultipliersModal component with:
  - User search and add with email autocomplete
  - Editable rate column with local edit mode (cancel/save)
  - Batch adjust: multiply all rates by a factor
  - Clear all (local operation, requires save to persist)
  - Pagination (10/20/50 per page)
  - Platform icon with brand colors in group info bar
  - Unsaved changes indicator with revert option
- Unit tests for all three backend endpoints

- Add configurable spending limit (quota_limit) for apikey-type accounts
- Atomic quota accumulation via PostgreSQL JSONB operations on TotalCost
- Scheduler filters out over-quota accounts with outbox-triggered snapshot refresh
- Display quota usage ($used / $limit) in account capacity column
- Add "Reset Quota" action in account menu to reset usage to zero
- Editing account settings preserves quota_used (no accidental reset)
- Covers all 3 billing paths: Anthropic, Gemini, OpenAI RecordUsage

chore: bump version to 0.1.90.4

The response interceptor in client.ts transforms errors into plain
objects {status, code, message}, but catch blocks were checking
error.response?.status (AxiosError format) which never matched.

- Add error field passthrough in client.ts interceptor
- Refactor BulkEditAccountModal to use pre-check API (checkMixedChannelRisk)
  before submit, matching the single edit flow
- Fix EditAccountModal catch blocks to use interceptor error format
- Add bulk-update mixed channel unit tests

## 核心功能
- 添加 AdminUpdateAPIKeyGroupID 服务方法，支持绑定/解绑/保持不变三态语义
- 实现 UserRepository.AddGroupToAllowedGroups 接口，自动同步专属分组权限
- 添加 HTTP PUT /api-keys/:id handler 端点，支持管理员直接修改 API Key 分组

## 事务一致性
- 使用 ent Tx 保证专属分组绑定时「添加权限」和「更新 Key」的原子性
- Repository 方法支持 clientFromContext，兼容事务内调用
- 事务失败时自动回滚，避免权限孤立

## 业务逻辑
- 订阅类型分组阻断，需通过订阅管理流程
- 非活跃分组拒绝绑定
- 负 ID 和非法 ID 验证
- 自动授权响应，告知管理员成功授权的分组

## 代码质量
- 16 个单元测试覆盖所有业务路径和边界用例
- 7 个 handler 集成测试覆盖 HTTP 层
- GroupRepo stub 返回克隆副本，防止测试间数据泄漏
- API 类型安全修复（PaginatedResponse<ApiKey>）
- 前端 ref 回调类型对齐 Vue 规范

## 国际化支持
- 中英文提示信息完整
- 自动授权成功/失败提示

- 新增 PUT /api/v1/admin/api-keys/:id 端点，允许管理员修改任意用户 API Key 的分组绑定
- 跳过用户级权限校验但保留分组有效性验证，修改后触发认证缓存失效
- Service 层支持三态语义：nil=不修改，0=解绑，>0=绑定，<0=拒绝
- 指针值拷贝保证安全隔离，负数 groupID 返回 400 INVALID_GROUP_ID
- 前端 UserApiKeysModal 新增可点击的分组选择下拉框，支持多 Key 并发更新
- 下拉支持视口翻转和滚动关闭，按钮有 disabled 和加载状态
- 覆盖：后端 20 个单元测试 (Service 11 + Handler 9) + 前端 16 个 E2E 测试
- golangci-lint 0 issues, make test-unit 全部通过

Add a dedicated CheckMixedChannel endpoint that allows the frontend
to pre-validate mixed channel risk before submitting create/update
requests. This improves UX by showing warnings earlier in the flow
instead of only after form submission.

Backend changes:
- Add CheckMixedChannelRequest struct and CheckMixedChannel handler
- Register POST /check-mixed-channel route
- Expose CheckMixedChannelRisk as public method on AdminService
- Simplify Create/Update 409 responses (remove details/require_confirmation)
- Add comprehensive handler tests and stub methods

Frontend changes:
- Add checkMixedChannelRisk API function and TypeScript types
- Refactor CreateAccountModal to precheck before step transition and submission
- Refactor EditAccountModal to precheck before update submission
- Replace pendingPayload pattern with action-based dialog flow

- Add groupID parameter to ListAccounts and ListWithFilters methods
- Implement account filtering by group ID in repository query
- Add group query parameter parsing in account handler
- Update all ListAccounts/ListWithFilters call sites with groupID parameter
- Add group filter UI component to AccountTableFilters
- Add i18n translations for group filter label in English and Chinese
- Update API contract and test stubs to reflect new signature
- Enable filtering accounts by their assigned groups in admin panel

- Add `sort_order` field to groups table with migration
- Add `PUT /api/v1/admin/groups/sort-order` API for batch update
- Implement drag-and-drop UI using vue-draggable-plus
- All queries now order groups by sort_order
- Add i18n support (en/zh) for sort-related UI text
- Update test stubs to satisfy new interface methods

Add ListByUserPaginated and SumPositiveBalanceByUser to redeemRepoStub
Add GetUserBalanceHistory to stubAdminService

Fixes CI test compilation errors