Phase 0.2: migrate remaining SVGs to lucide-react icons

frontend/src/components/dms/UploadDropzone.tsx

@@ -8,6 +8,7 @@ import clsx from 'clsx';
 import { useTranslation } from 'react-i18next';
 import { uploadFile } from '@/api/dms';
 import { useToast } from '@/components/ui/Toast';
+import { Upload } from 'lucide-react';
 
 export interface UploadDropzoneProps {
   folderId: string | null;
@@ -124,9 +125,7 @@ export function UploadDropzone({ folderId, onUploaded }: UploadDropzoneProps) {
           className="hidden"
           aria-hidden="true"
         />
-        <svg className="mx-auto h-10 w-10 text-secondary-400" fill="none" viewBox="0 0 24 24" stroke="currentColor" aria-hidden="true">
-          <path strokeLinecap="round" strokeLinejoin="round" strokeWidth={1.5} d="M7 16a4 4 0 01-.88-7.903A5 5 0 1115.9 6L16 6a5 5 0 011 9.9M15 13l-3-3m0 0l-3 3m3-3v12" />
-        </svg>
+        <Upload className="mx-auto h-10 w-10 text-secondary-400" aria-hidden="true" strokeWidth={1.5} />
         <p className="mt-2 text-sm text-secondary-600">{t('dms.uploadDropHere')}</p>
       </div>
       {uploads.length > 0 && (