I have a similar system. I keep my wip.md open in Neovim all the time and the difference is: everyday, I move the done items to a timestamped file. I have records going back to 2009.
It's my timelog and work journal as I expand on items and mark them off as I work on them.
Incidently, I was exploring new ways to work with it recently: https://bsky.app/profile/did:plc:bryys25pc2fnagnyxqgsglhd/po...