I've actually been doing this for a year. I call it /checkpoint instead and it does some thing like:

* update our architecture.md and other key md files in folders affected by updates and learnings in this session. * update claude.md with changes in workflows/tooling/conventions (not project summaries) * commit

It's been pretty good so far. Nothing fancy. Recently I also asked to keep memories within the repo itself instead of in ~/.claude.

Only downside is it is slow but keeps enough to pass the baton. May be "handoff" would have been a better name!