fix(P2): 修复 import cycle — 将 apierror 移出 internal/http 避免循环依赖

backend/internal/http/errors.go

@@ -1,28 +0,0 @@
-package http
-
-import (
-	"errors"
-	"net/http"
-
-	"gorm.io/gorm"
-)
-
-var (
-	ErrUnauthorized = errors.New("unauthorized")
-	ErrValidation   = errors.New("validation error")
-)
-
-func ClassifyHTTPStatus(err error) int {
-	switch {
-	case err == nil:
-		return http.StatusOK
-	case errors.Is(err, ErrUnauthorized):
-		return http.StatusUnauthorized
-	case errors.Is(err, ErrValidation):
-		return http.StatusBadRequest
-	case errors.Is(err, gorm.ErrRecordNotFound):
-		return http.StatusNotFound
-	default:
-		return http.StatusInternalServerError
-	}
-}