roadmap

## Start Announce: **"Checking for in-progress runs and roadmap layout…"** Read @CLAUDE.md. ## Per-Phase Checklist File One checklist per `/roadmap` run, created right after step 2a (branch checkout succeeded), updated at the end of every subsequent step. The checklist lives at `docs/roadmap/plans/YYYY-MM-DD-<topic>-checklist.md` — alongside the design and plan files for the same run. ### Filename `YYYY-MM-DD-<phase-slug>-checklist.md`, where `<phase-slug>` is the **phase filename slug** (defined immediately below), and `YYYY-MM-DD` is the day step 0 → step 1 fires (start date) — so the design / plan / checklist for one run sit alphabetically adjacent in `plans/`. #### Phase filename slug A single rule, used by checklist filenames here and referenced from §2a and §Appendix: 1. Take the phase title text (everything after the `Phase N:` or `Phase Na:` prefix in the roadmap heading). 2. Lowercase. 3. Drop apostrophes (`'`, `'`, `'`) **without** inserting a separator (so `Editor's` becomes `editors`, not `editor-s`). 4. Replace any run of non-`[a-z0-9]` characters with a single hyphen. 5. Strip leading and trailing hyphens. 6. If the result is empty (e.g. the title was only Unicode/CJK characters that collapsed to nothing), fall back to `phase-N` using the phase number — including any sub-letter — from the heading. `Phase 3a: 漢字` → `phase-3a`. Examples: | Phase heading | Phase filename slug | |--------------------------...