Check git worktrees and peer sessions before editing docs

In a repo where several Claude sessions run, the folder you were started in can be a stale local main while origin/main already holds a rewrite from a peer session's worktree. Run git fetch, git log origin/main and git worktree list before editing READMEs or posts, because the user may assume a different version than the one on disk. In this case the user thought the project used real Kaggle data, but local main still had the old synthetic generator. Stash edits that target the stale version, ask the peer session over SendMessage which files it is touching, and when a dashboard JSON is generated by a script that CI diffs, edit the generator rather than the JSON.