Problem: Cannot detect whether modifyOtherKeys is enabled.
Solution: Use XTQMODKEYS introduced by xterm version 377 to request the
modifyOtherKeys level. Update the keycode check results.
Problem: Cannot debug the Kitty keyboard protocol with TermDebug.
Solution: Add Kitty keyboard protocol support to the libvterm fork.
Recognize the escape sequences that the protocol generates. Add
the 'keyprotocol' option to allow the user to specify for which
terminal what protocol is to be used, instead of hard-coding this.
Add recognizing the kitty keyboard protocol status.
Problem: libvterm with modifyOtherKeys level 2 does not match xterm.
Solution: Adjust key code escape sequences to be the same as what xterm
sends in modifyOtherKeys level 2 mode. Check the value of
no_reduce_keys before using it.
Problem: Keycode check script has a few flaws.
Solution: Sort on terminal name. Ignore XTGETTCAP responses. Check for
version and status response. Update entries.
Problem: Cannot easily try out what codes various keys produce.
Solution: Add a script to gather key code information, with an initial list
of codes to compare with.
