Don't keep progress in the conversation, keep it in a file. For anything over ~5 files I start with:
Write a checklist of every file to migrate to
MIGRATION.md. After each file, tick it off in that file. Before starting a file, readMIGRATION.md.
Now it doesn't matter whether you /compact, /clear or come back tomorrow: the state is on disk and in git. Commit after every 2–3 ticked files, so a bad revert is a git diff away from being spotted.
Nadia's instruction trick is good too, but a file survives things a summary doesn't.