Rebase theme branches onto main

Each theme-* branch is one commit on top of main: the theme's own theme NNN: … commit (README, "Themes"). theme-rebase.sh rebuilds every theme that way on the current main. For each theme, in its own worktree, it:

1. squash-merges the theme onto main: one 3-way merge, however many commits the branch has;
2. settles what needs no judgment: bun.lock, package.json, and every path only copied commits touched, which take main's side; then runs the codemods over the merged files and over both sides of each remaining conflict, so a rewrite main made everywhere stops conflicting with the theme's edits around it;
3. starts one headless Claude session for what is left, with rules.md as its instructions;
4. runs bun run check and bun run build, resuming the session once on a failure;
5. commits with the theme commit's message and author, and sends anything doubtful to review.

Nothing leaves the machine until push.

Run it

S=.agents/skills/theme-rebase/theme-rebase.sh
bash $S run theme-002 theme-003   # or --all
bash $S push                      # the last run's ok themes, one at a time
bash $S clean [theme…]            # drop leftover worktrees and theme-rebase/* branches

The build reads live store data, so it needs YNS_API_KEY in .env. A free census of what a run would hit: AGENT=none BUILD=0 bash $S run --all.

Roll a large run out in batches of about 20: run, read the table, push, then the next batch. A scheduled run is run --all, then push, then the table as the report.

Statuses

results.jsonl in the run directory (printed under the table) holds every row: the session id, the theme commit, the conflicts by kind and the kept worktree.

Policy

• A theme's own commits have a theme NNN: … subject. Every other commit on a theme branch counts as a copy of a main change, and wherever it conflicts, main's side wins. Make cross-cutting fixes on main, never on theme branches.
• A change on main that renames or retires something themes use ships with a codemod: an executable codemods/<name>.sh that rewrites the files it is given in place, the way the main commit did, and leaves every other file byte-identical. Check it the way yns-link.sh was checked: run it, plus bun biome check --write --unsafe, over the parent of that commit's files, and it must reproduce the commit's versions.
• run never overwrites an earlier result: a theme with a theme-rebase/<theme> branch is skipped until it is pushed or cleaned.
• Never modify main from this skill. push writes only theme-* branches and backup/* tags, atomically, leased on the tip the run started from.
• Each theme push starts a Vercel preview build, which is why push goes one theme at a time.
• Local theme-* branches go stale after a push: delete them, or reset them to origin/<theme>.