feat: 实现密码重置功能与用户搜索API，优化注册登录流程

- 新增忘记密码页面与重置密码确认流程（前端+后端）
- 修复注册验证码页登录跳转路由
- 新增用户搜索API（按邮箱查询）
- 简化infra脚本，统一为app.sh
- 补充密码重置与用户API测试覆盖
- 更新runtime文档与AGENTS配置

backend/src/v1/users/router.py

@@ -2,10 +2,10 @@ from __future__ import annotations
 
 from typing import Annotated
 
-from fastapi import APIRouter, Depends, Path
+from fastapi import APIRouter, Depends
 
 from v1.users.dependencies import get_user_service
-from v1.users.schemas import UserResponse, UserUpdateRequest
+from v1.users.schemas import UserResponse, UserSearchRequest, UserUpdateRequest
 from v1.users.service import UserService
 
 
@@ -27,11 +27,9 @@ async def update_me(
     return await service.update_me(payload)
 
 
-@router.get("/{username}", response_model=UserResponse)
-async def get_by_username(
-    username: Annotated[
-        str, Path(min_length=3, max_length=30, pattern="^[a-zA-Z0-9_]+$")
-    ],
+@router.post("/search", response_model=list[UserResponse])
+async def search_users(
+    payload: UserSearchRequest,
     service: Annotated[UserService, Depends(get_user_service)],
-) -> UserResponse:
-    return await service.get_by_username(username)
+) -> list[UserResponse]:
+    return await service.search_users(payload)