fix(adminfront): prevent bulk import modal from unmounting when dropdown closes

Lifted the modal state out of the DropdownMenuContent to ensure the dialog does not unmount immediately when the dropdown item is clicked.

adminfront/src/features/users/components/UserBulkUploadModal.tsx

@@ -43,7 +43,9 @@ import {
 
 interface UserBulkUploadModalProps {
   onSuccess?: () => void;
-  variant?: "button" | "dropdown";
+  variant?: "button" | "dropdown" | "custom";
+  open?: boolean;
+  onOpenChange?: (open: boolean) => void;
 }
 
 function buildUserTenantPreviewRows(
@@ -141,8 +143,15 @@ export const downloadUserTemplate = () => {
 export function UserBulkUploadModal({
   onSuccess,
   variant = "button",
+  open: controlledOpen,
+  onOpenChange: controlledOnOpenChange,
 }: UserBulkUploadModalProps) {
-  const [open, setOpen] = React.useState(false);
+  const [localOpen, setLocalOpen] = React.useState(false);
+  const open = controlledOpen !== undefined ? controlledOpen : localOpen;
+  const setOpen = (val: boolean) => {
+    setLocalOpen(val);
+    controlledOnOpenChange?.(val);
+  };
   const [file, setFile] = React.useState<File | null>(null);
   const [parsing, setParsing] = React.useState(false);
   const [previewData, setPreviewData] = React.useState<BulkUserItem[]>([]);
@@ -359,7 +368,7 @@ export function UserBulkUploadModal({
         <Upload size={16} className="mr-2 opacity-50" />
         {t("ui.admin.users.list.bulk_import", "일괄 등록 (CSV)")}
       </DropdownMenuItem>
-    ) : (
+    ) : variant === "custom" ? null : (
       <DialogTrigger asChild>
         <Button variant="outline" className="gap-2" {...triggerProps}>
           <Upload size={16} />
@@ -378,7 +387,7 @@ export function UserBulkUploadModal({
           if (!val) reset();
         }}
       >
-        {variant !== "dropdown" && triggerNode}
+        {variant !== "dropdown" && variant !== "custom" && triggerNode}
         <DialogContent className="max-w-2xl">
           <DialogHeader>
             <DialogTitle data-testid="bulk-upload-title">