fix: 解决应用安装 services 为空报系统错误的问题 (#5445)

backend/app/service/app.go

@@ -367,7 +367,7 @@ func (a AppService) Install(ctx context.Context, req request.AppInstallCreate) (
 	}
 
 	value, ok := composeMap["services"]
-	if !ok {
+	if !ok || value == nil {
 		err = buserr.New(constant.ErrFileParse)
 		return
 	}

backend/app/service/app_utils.go

@@ -449,7 +449,7 @@ func getUpgradeCompose(install model.AppInstall, detail model.AppDetail) (string
 		return "", err
 	}
 	value, ok := composeMap["services"]
-	if !ok {
+	if !ok || value == nil {
 		return "", buserr.New(constant.ErrFileParse)
 	}
 	servicesMap := value.(map[string]interface{})

backend/app/service/website_utils.go

@@ -863,7 +863,7 @@ func changeServiceName(newComposeContent, newServiceName string) (composeByte []
 		return
 	}
 	value, ok := composeMap["services"]
-	if !ok {
+	if !ok || value == nil {
 		err = buserr.New(constant.ErrFileParse)
 		return
 	}