5-retrolisted

# /5-retro — retro Input: a work unit slug. ## Steps 1. **Create the retro branch:** from the primary checkout, run `bash scripts/worktree.sh add retro-<slug>` and work in the returned worktree on branch `wt/retro-<slug>`. If the worktree already exists, reuse it instead of running worktree.sh add again. 2. **Answer the four questions:** - What did the gate miss that a reviewer caught? - What did every check miss? - What got re-derived that a doc would have prevented? - What friction repeated from a prior retro? 3. **Route each answer to exactly one label:** - `mechanical` — a `gate.d/` hook or script fix. - `contextual` — a `knowledge/` doc, following `knowledge/README.md`: the doc that would have prevented this instance, no bigger. - `process` — one line in `PLAN.md` under Decisions. - `not worth keeping` — say so explicitly, with why. 4. **Write the retro:** create `work/<slug>/retro.md` on the retro branch. "Nothing learned" is a valid one-line retro. 5. **Apply every routing on the retro branch.** An unapplied routing means the stage is not done. 6. **Respect the mechanical file boundary:** the retro branch may only touch `knowledge/`, `PLAN.md`, and `work/<slug>/retro.md`. Any routing that would edit `scripts/` or `gate.d/` becomes a `/1-plan` unit named in the retro instead of being applied here. 7. **Publish for review:** push `wt/retro-<slug>` and open a PR to `main`. 8. **Clean up after merge:** run `bash scripts/worktree.sh remove retro-<