fix: Block creating files with non-existing parent directories using O_CREATE

cmd/stfs/cmd/serve_ftp.go

@@ -193,7 +193,7 @@ var serveFTPCmd = &cobra.Command{
 				)
 			},
 			viper.GetBool(readOnlyFlag),
-			true, // FTP requires read permission even if `O_WRONLY` is set if cache is enabled
+			true, // FTP requires read permission even if `O_WRONLY` is set if cache is enabled, as the cache needs to read the written file
 
 			func(hdr *config.Header) {
 				jsonLogger.Trace("Header transform", hdr)