A changelog and a roadmap

CHANGELOG.md keeps what has changed since the last version, a line per
fix or addition the day it lands, with credit to whoever made it; at
release its gist becomes NOTES.md and the update that gets posted. It
starts with the six pull requests merged today and the typing beep.

ROADMAP.md is everything asked for since the launch, from the issues,
the pull requests and the replies on X, sorted into fixes for the next
update, small additions, bigger work, and what isn't on the list and
why.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>