feat(auth+db): 实现注册登录核心逻辑，以及自动建表，用户信息落库

backend/internal/handler/register.go

@@ -4,15 +4,23 @@ import (
 	"net/http"
 
 	"gen2d/internal/model"
+	"gen2d/internal/service"
 
 	"github.com/gin-gonic/gin"
 )
 
+var authSvc *service.AuthService
+
+// InitAuthService 由 main 在启动时调用，注入 JWT 配置。
+func InitAuthService(jwtSecret string, jwtExpire int64) {
+	authSvc = service.NewAuthService(jwtSecret, jwtExpire)
+}
+
 // RegisterRequest 注册请求参数。
 type RegisterRequest struct {
-	Username string `json:"username" binding:"required,min=3,max=32"` // 用户名
-	Password string `json:"password" binding:"required,min=6,max=64"` // 密码
-	Email    string `json:"email" binding:"omitempty,email"`           // 邮箱（可选）
+	Username string `json:"username" binding:"required,min=3,max=32"`
+	Password string `json:"password" binding:"required,min=6,max=64"`
+	Email    string `json:"email" binding:"omitempty,email"`
 }
 
 // RegisterResponse 注册成功返回的用户信息。
@@ -29,9 +37,14 @@ func Register(c *gin.Context) {
 		return
 	}
 
-	// TODO: 调用 service 层创建用户
+	user, err := authSvc.Register(c.Request.Context(), req.Username, req.Password, req.Email)
+	if err != nil {
+		c.JSON(http.StatusConflict, model.Fail(http.StatusConflict, err.Error()))
+		return
+	}
+
 	c.JSON(http.StatusCreated, model.OK(RegisterResponse{
-		ID:       0,
-		Username: req.Username,
+		ID:       user.ID,
+		Username: user.Username,
 	}))
 }