Possible security issue: backup wallet files are not removed and are accessible

[Satoshinaire]

It would be nice if the UI could clean up the backup files, and even better if they weren't in a web-accessible path, but rather served via a token.

Currently, I can browse and download my wallet.dat file from an unauthenticated session.

While this is not as bad as it could be, because the wallet filename is obfuscated with the number prefix, anyone else using my computer seeing my browser history might be able to still get access.