feat: Add public user information retrieval endpoint

- Introduced a new endpoint to fetch public user information without authentication.
- Implemented UserToPublicUserInfo function to format user data for the response.
- Updated UserService interface and user service implementation to support fetching users by username.
- Enhanced user handler to validate input parameters and check user status before responding.

internal/handler/helpers.go

@@ -62,6 +62,19 @@ func UserToUserInfo(user *model.User) *types.UserInfo {
 	}
 }
 
+// UserToPublicUserInfo 将 User 模型转换为 PublicUserInfo 响应
+func UserToPublicUserInfo(user *model.User) *types.PublicUserInfo {
+	return &types.PublicUserInfo{
+		ID:        user.ID,
+		Username:  user.Username,
+		Avatar:    user.Avatar,
+		Points:    user.Points,
+		Role:      user.Role,
+		Status:    user.Status,
+		CreatedAt: user.CreatedAt,
+	}
+}
+
 // ProfileToProfileInfo 将 Profile 模型转换为 ProfileInfo 响应
 func ProfileToProfileInfo(profile *model.Profile) *types.ProfileInfo {
 	return &types.ProfileInfo{

internal/handler/routes.go

@@ -93,6 +93,10 @@ func registerAuthRoutes(v1 *gin.RouterGroup, h *AuthHandler) {
 
 // registerUserRoutes 注册用户路由
 func registerUserRoutes(v1 *gin.RouterGroup, h *UserHandler, jwtService *auth.JWTService) {
+	// 公开用户信息路由（无需认证）
+	v1.GET("/users/public", h.GetPublicInfo)
+
+	// 需要认证的用户路由
 	userGroup := v1.Group("/user")
 	userGroup.Use(middleware.AuthMiddleware(jwtService))
 	{

internal/handler/user_handler.go

@@ -2,6 +2,7 @@ package handler
 
 import (
 	"carrotskin/internal/container"
+	"carrotskin/internal/model"
 	"carrotskin/internal/service"
 	"carrotskin/internal/types"
 
@@ -315,3 +316,55 @@ func (h *UserHandler) ResetYggdrasilPassword(c *gin.Context) {
 	h.logger.Info("Yggdrasil密码重置成功", zap.Int64("userId", userID))
 	RespondSuccess(c, gin.H{"password": newPassword})
 }
+
+// GetPublicInfo 获取用户公开信息
+// @Summary 获取用户公开信息
+// @Description 根据用户名或用户ID获取用户的公开信息（不包含敏感信息如邮箱）
+// @Tags user
+// @Accept json
+// @Produce json
+// @Param username query string false "用户名"
+// @Param id query int false "用户ID"
+// @Success 200 {object} model.Response{data=types.PublicUserInfo} "获取成功"
+// @Failure 400 {object} model.ErrorResponse "参数错误"
+// @Failure 404 {object} model.ErrorResponse "用户不存在"
+// @Router /api/v1/users/public [get]
+func (h *UserHandler) GetPublicInfo(c *gin.Context) {
+	username := c.Query("username")
+	idStr := c.Query("id")
+
+	// 至少需要提供一个参数
+	if username == "" && idStr == "" {
+		RespondBadRequest(c, "必须提供用户名或用户ID", nil)
+		return
+	}
+
+	var user *model.User
+	var err error
+
+	// 优先使用用户名查询
+	if username != "" {
+		user, err = h.container.UserService.GetByUsername(c.Request.Context(), username)
+	} else {
+		// 使用用户ID查询
+		id := parseIntWithDefault(idStr, 0)
+		if id == 0 {
+			RespondBadRequest(c, "无效的用户ID", nil)
+			return
+		}
+		user, err = h.container.UserService.GetByID(c.Request.Context(), int64(id))
+	}
+
+	if err != nil || user == nil {
+		RespondNotFound(c, "用户不存在")
+		return
+	}
+
+	// 检查用户状态
+	if user.Status != 1 {
+		RespondNotFound(c, "用户不可用")
+		return
+	}
+
+	RespondSuccess(c, UserToPublicUserInfo(user))
+}

internal/service/interfaces.go

@@ -19,6 +19,7 @@ type UserService interface {
 	// 用户查询
 	GetByID(ctx context.Context, id int64) (*model.User, error)
 	GetByEmail(ctx context.Context, email string) (*model.User, error)
+	GetByUsername(ctx context.Context, username string) (*model.User, error)
 
 	// 用户更新
 	UpdateInfo(ctx context.Context, user *model.User) error

internal/service/user_service.go

@@ -199,6 +199,14 @@ func (s *userService) GetByEmail(ctx context.Context, email string) (*model.User
 	}, s.cache.Policy.UserEmailTTL)
 }
 
+func (s *userService) GetByUsername(ctx context.Context, username string) (*model.User, error) {
+	// 使用 Cached 装饰器自动处理缓存
+	cacheKey := s.cacheKeys.UserByUsername(username)
+	return database.Cached(ctx, s.cache, cacheKey, func() (*model.User, error) {
+		return s.userRepo.FindByUsername(ctx, username)
+	}, s.cache.Policy.UserTTL)
+}
+
 func (s *userService) UpdateInfo(ctx context.Context, user *model.User) error {
 	err := s.userRepo.Update(ctx, user)
 	if err != nil {

internal/types/common.go

@@ -110,6 +110,18 @@ type UserInfo struct {
 	UpdatedAt   time.Time  `json:"updated_at" example:"2025-10-01T10:00:00Z"`
 }
 
+// PublicUserInfo 用户公开信息
+// @Description 用户公开信息（不包含敏感信息如邮箱）
+type PublicUserInfo struct {
+	ID        int64     `json:"id" example:"1"`
+	Username  string    `json:"username" example:"testuser"`
+	Avatar    string    `json:"avatar" example:"https://example.com/avatar.png"`
+	Points    int       `json:"points" example:"100"`
+	Role      string    `json:"role" example:"user"`
+	Status    int16     `json:"status" example:"1"`
+	CreatedAt time.Time `json:"created_at" example:"2025-10-01T10:00:00Z"`
+}
+
 // TextureType 材质类型
 type TextureType string