refactor: 移除前端 Mock API，新增共享组件，优化认证流程

- 删除 mock_api_client、mock_calendar_service、mock_history_service
- 新增 fixed_length_code_input、link_button、message_composer 共享组件
- 优化登录/注册/密码重置页面使用新组件
- 简化 injection.dart 移除 mock 分支
- 更新 env.dart 配置（BACKEND_URL 替换 API_URL）
- 后端 agentscope 工具和测试更新
- 重构 AGENTS.md 文档结构
- 新增 deploy/ 目录和 protocol 文档

docs/protocols/routes.md

@@ -0,0 +1,13 @@
+# Auth Routes Protocol Notes
+
+## POST `/api/v1/auth/verifications`
+
+- `invite_code` is optional.
+- Recommended format is fixed `4` chars and pattern `^[ABCDEFGHJKMNPQRSTUVWXYZ23456789]{4}$`.
+- Backend normalizes invite codes to uppercase and validates in service logic.
+- Invalid invite code values are ignored (treated as empty), and signup verification email flow still continues.
+
+## Verification Token Input Convention
+
+- Verification token for signup/recovery uses fixed `6` digits.
+- Client UI should use fixed-length segmented input to reduce mistyped values.