One-line fix is much shorter than attempting to describe the problem.
^A could misuse previous input if 'f'<direction> needed to fill the
quiver and there was nothing suitable, so that the sequence became
'f'<what to throw>. If previous <direction> was an inventory letter
that was occupied, and the item it that slot wasn't already worn in
some other slot, it would be put in quiver slot. Then player would
be asked for direction rather than immediately throwing it since the
what-to-throw prompt had just used up the last of the ^A queue.
Miscellaneous formatting included....
9c4a6afe46