feat: 实现用户注册功能，包括数据库表结构、gRPC 服务和业务逻辑

backend/services/user-svc/internal/service/service.go

@@ -0,0 +1,39 @@
+package service
+
+import (
+	"backend/services/user-svc/internal/domain"
+	"backend/services/user-svc/internal/repository"
+	"backend/shared/pkg/errors"
+)
+
+type UserService struct {
+	repo *repository.UserRepository
+}
+
+func NewUserService(repo *repository.UserRepository) *UserService {
+	return &UserService{repo: repo}
+}
+
+// Register 用户注册
+func (s *UserService) Register(req *domain.RegisterRequest) (*domain.RegisterResponse, error) {
+	// 验证请求参数
+	if req.Account == "" {
+		return nil, errors.ErrInvalidInput
+	}
+
+	if len(req.Password) < 6 {
+		return nil, errors.ErrInvalidInput
+	}
+
+	// 调用仓库层注册用户
+	return s.repo.Register(req)
+}
+
+// GetUserByAccount 根据账号获取用户信息
+func (s *UserService) GetUserByAccount(account string) (*domain.User, *domain.UserLoginAccount, *domain.UserLoginPassword, error) {
+	if account == "" {
+		return nil, nil, nil, errors.ErrInvalidInput
+	}
+
+	return s.repo.GetUserByAccount(account)
+}