Add an actcompactbutton colour set so focused compact buttons can be styled separately from inactive compact buttons.
Proposed behaviour: actcompactbutton should be optional and fall back to compactbutton when unset, preserving existing themes. This would let NEWT_COLORS style focused compact buttons independently, e.g. compactbutton=white,black;actcompactbutton=black,white. This is particularly useful for whiptail --yesno dialogs, which use compact buttons. An implementation should avoid breaking Newt’s existing public C API/ABI; a dedicated setter may be preferable to extending a public palette structure directly.
Created PR #37 for consideration.