feat: Enhance error handling with showErrorToast utility

- Replaced existing toast error messages with the new `showErrorToast` utility across multiple components, improving consistency in error reporting.
- Updated error messages to provide more specific guidance for users, enhancing the overall user experience during error scenarios.
- Ensured that all relevant error handling in batch management, external call configurations, cascading management, and screen management components now utilizes the new utility for better maintainability.

frontend/lib/registry/components/file-upload/FileUploadComponent.tsx

@@ -3,6 +3,7 @@ import { Card, CardContent } from "@/components/ui/card";
 import { Button } from "@/components/ui/button";
 import { Badge } from "@/components/ui/badge";
 import { toast } from "sonner";
+import { showErrorToast } from "@/lib/utils/toastUtils";
 import { uploadFiles, downloadFile, deleteFile, getComponentFiles } from "@/lib/api/file";
 import { GlobalFileManager } from "@/lib/api/globalFile";
 import { formatFileSize } from "@/lib/utils";
@@ -881,7 +882,7 @@ const FileUploadComponent: React.FC<FileUploadComponentProps> = ({
         console.error("파일 업로드 오류:", error);
         setUploadStatus("error");
         toast.dismiss("file-upload");
-        toast.error(`파일 업로드 오류: ${error instanceof Error ? error.message : "알 수 없는 오류"}`);
+        showErrorToast("파일 업로드에 실패했습니다", error, { guidance: "파일 크기와 형식을 확인하고 다시 시도해 주세요." });
       }
     },
     [safeComponentConfig, uploadedFiles, onFormDataChange, component.columnName, component.id, formData],
@@ -1006,7 +1007,7 @@ const FileUploadComponent: React.FC<FileUploadComponentProps> = ({
         toast.success(`${fileName} 삭제 완료`);
       } catch (error) {
         console.error("파일 삭제 오류:", error);
-        toast.error("파일 삭제에 실패했습니다.");
+        showErrorToast("파일 삭제에 실패했습니다", error, { guidance: "잠시 후 다시 시도해 주세요." });
       }
     },
     [uploadedFiles, onUpdate, component.id, isRecordMode, onFormDataChange, recordTableName, recordId, columnName, getUniqueKey],