fix: decode multer filename encoding for non-ASCII filenames

server/src/routes/collab.ts

@@ -39,6 +39,7 @@ const noteUpload = multer({
     filename: (_req, file, cb) => { cb(null, `${uuidv4()}${path.extname(file.originalname)}`) },
   }),
   limits: { fileSize: MAX_NOTE_FILE_SIZE },
+  defParamCharset: 'utf8',
   fileFilter: (_req, file, cb) => {
     const ext = path.extname(file.originalname).toLowerCase();
     const BLOCKED = ['.svg', '.html', '.htm', '.xml', '.xhtml', '.js', '.jsx', '.ts', '.exe', '.bat', '.sh', '.cmd', '.msi', '.dll', '.com', '.vbs', '.ps1', '.php'];

server/src/routes/files.ts

@@ -38,6 +38,7 @@ function getAllowedExtensions(): string {
 const upload = multer({
   storage,
   limits: { fileSize: MAX_FILE_SIZE },
+  defParamCharset: 'utf8',
   fileFilter: (_req, file, cb) => {
     const ext = path.extname(file.originalname).toLowerCase();
     if (BLOCKED_EXTENSIONS.includes(ext) || file.mimetype.includes('svg')) {