* feat(#2544): add API for querying win ID, api.tree.winid() * Document winid() opts Co-authored-by: Alexander Courtis <alex@courtis.org> * Fix winid() docs Co-authored-by: Alexander Courtis <alex@courtis.org> * Handle case where tabpage = 0 --------- Co-authored-by: Alexander Courtis <alex@courtis.org>