fix: 修复后端代码违规并更新协议文档

- 修复 notifications 模块 datetime.now() 缺少时区问题
- 用 ApiProblemError 替换 BaseService 中的 HTTPException
- 更新协议文档：添加错误码、繁体字段、邀请相关协议
- 升级 Docker 镜像版本

docs/protocols/common/http-error-codes.md

@@ -83,6 +83,12 @@ This document is the source of truth for backend RFC7807 `code` values consumed
 |---|---:|---|---|
 | `NOTIFICATION_NOT_FOUND` | 404 | Notification not found or not owned by current user | Show not-found message and refresh list |
 
+## Invite
+
+| code | status | meaning | frontend handling |
+|---|---:|---|---|
+| `INVITE_CODE_NOT_FOUND` | 404 | Invite code not found for current user | Show not-found message and trigger invite code bootstrap |
+
 ## Global
 
 | code | status | meaning | frontend handling |

docs/protocols/common/user-points-chat-data-protocol.md

@@ -39,12 +39,15 @@ Protocol verification status:
 ### profiles
 
 - PK: `id` (`auth.users.id`, `on delete cascade`)
-- Core fields: `username`, `avatar_url`, `bio`, `settings`, `created_at`, `updated_at`, `deleted_at`
+- Core fields: `username`, `avatar_url`, `bio`, `settings`, `referred_by`, `created_at`, `updated_at`, `deleted_at`
 - Constraints:
   - `username` not empty
 - Indexes:
   - `ix_profiles_username`
   - `ix_profiles_settings_gin`
+- Notes:
+  - `referred_by` is FK to `profiles.id` (`on delete set null`) for invite/referral tracking
+  - `settings` stores `ProfileSettingsV1` JSON including `preferences`, `privacy`, `notification`, `divination_tutorial`
 
 ### user_points