Fix TypeError: file_area.lib_list[i].dir is undefined

dir is not a property of lib_list[], appears to be a typo.

Also, in the "lib" scope commands, j was not defined.

The offline_dir property appears to have been deprecated (no longer
enumerable) years ago, in favor of the dir/dir_list[].is_offline
property, so use that property instead for skipping offline dirs.
Reported by xbit (XBITBBS)

Also, make sure the ;upload and other lib/all search commands are
abortable with Ctrl-C.