EOF (Ctrl-D) does not exit interpreter

The interpreter does not cleanly exit upon receiving an EOF, instead treating it as a command:

% pkpass
Welcome to PKPass (Public Key Based Password Manager) v2.7.8!
Type ? to list commands
pkpass> ^DCommand 'EOF' not found, see help (?) for available commands
pkpass>

[ginsburgnm]

This is more of a feature than a bug, this allows you to kill a subcommand of the interpreter while remaining in the interpreter. The only supported way to exit it is exit

The initial reasoning for this was because when the program was originally developed use of badges was required, there were no yubikeys. Badges take forever on commands, so being able to kill the subcommand without having to reload the data from the computer was desired functionality.