fix+docs v1.21.1: audit of v1.16-v1.21

- fix: Split snaps the click to the room's nearest wall instead of the grid, so
  it works on non-grid-aligned rooms (imported/legacy polygons); the pull is
  capped (~6 cells) so accidental mid-room clicks stay a miss; splitRoom() still
  rejects a bad cut. closestPointOnBoundary() + unit test.
- docs: README (en+ru) documents Merge/Split/ruler/per-space scale (were undocumented);
  TESTING.md merge/split rows + fresh self-run; new smokes smoke_merge_split,
  smoke_split_nonsnap (incl. the capped-pull case).
- 73 frontend + 12 backend tests green; module eval + both cards register.

docs/CHANGELOG.md

@@ -1,5 +1,20 @@
 # Changelog
 
+## v1.21.1 — 2026-07-16 (audit: split snaps to the wall, docs for merge/split)
+- **Fix (found in audit):** Split required each click to land on a grid node, so it
+  silently refused rooms whose walls are not grid-aligned (imported or older polygons)
+  — the "pick a wall" toast fired no matter where you clicked. The click now snaps to
+  the room's nearest wall (`closestPointOnBoundary`) instead of the grid, with the pull
+  capped at ~6 grid cells so an accidental click in the middle of a room stays a miss
+  rather than becoming a wall point the user never meant; `splitRoom()` still rejects
+  a cut that is not a clean wall-to-wall chord. Also makes aiming easier on the fine
+  (240-cell) grid.
+- **Docs:** README (en + ru) now documents room Merge, Split, the drawing ruler and the
+  per-space scale — these v1.18–v1.21 features were shipped without user-facing docs.
+  `docs/TESTING.md` gained merge/split rows and a fresh self-run record.
+- New smokes `demo/smoke_merge_split.mjs` and `smoke_split_nonsnap.mjs`;
+  `closestPointOnBoundary` unit-tested. (+1 test: 72 → 73.)
+
 ## v1.21.0 — 2026-07-16 (merge and split rooms)
 - **Merge** (toolbar "Merge"): click a room, then a neighbour. Only rooms that **share a wall**
   can merge — and that is decided by the result rather than a heuristic: `mergeRooms` unions the

docs/STATUS.md

@@ -13,14 +13,14 @@
 
 | Item | State |
 |---|---|
-| Version | **v1.21.0** everywhere (manifest, const.py, package.json, CARD_VERSION) |
+| Version | **v1.21.1** everywhere (manifest, const.py, package.json, CARD_VERSION) |
 | GitHub | https://github.com/Matysh/houseplan-card — branch `main`, releases v1.9.3…v1.11.2 |
 | CI | `.github/workflows/validate.yml` (hacs + hassfest + frontend + backend) — **fully green** since v1.11.1; `release.yml` auto-attaches the card bundle (needs `permissions: contents: write`, fixed) |
 | HACS | Works as custom repository (id 1290210112 on the home instance). **Inclusion PR: https://github.com/hacs/default/pull/9004** (queue ≈2 months as of 2026-07). Lesson: #8995 was auto-closed by hacs-bot — the PR body MUST be their exact template with every checkbox ticked and all 3 links (release, HACS action run, hassfest run); a custom body gets closed without discussion |
 | Brands | Ships **inside the integration**: `custom_components/houseplan/brand/{icon,icon@2x,logo,logo@2x}.png` (HA ≥2026.3 local-brands mechanism). home-assistant/brands PR #10700 was auto-closed — that repo no longer accepts custom integrations |
 | Home instance | ha.jbstudio.pro (SSH port 323, key `ha_jb`), deployed v1.11.2, installed *via HACS* (custom repo) — updates flow through HACS now |
 | Localization | UI en/ru (`src/i18n.ts`), auto by `hass.locale` + `language` card option; codebase and docs are English-first (`README.ru.md` is the Russian copy) |
-| Tests | 72 frontend (node:test, incl. a 12-test buildDevices suite on a fake hass) + 10 pure backend (anywhere) + 12 HA-harness backend (CI only, py3.13; skipped locally — sandbox has py3.10) |
+| Tests | 73 frontend (node:test, incl. a 12-test buildDevices suite on a fake hass) + 10 pure backend (anywhere) + 12 HA-harness backend (CI only, py3.13; skipped locally — sandbox has py3.10) |
 
 ## Recent milestones (details in CHANGELOG.md)
 

docs/TESTING.md

@@ -79,6 +79,10 @@ Run the *core flows* (marked ★ below) in each environment at least once per mi
 - [ ] Split (v1.21.0): click a room, then two points on its walls — the bigger part keeps the
       name/area/devices, the smaller opens the new-room dialog; Cancel leaves the room whole
 - [ ] Split: a cut with an end off the wall, or along a wall, is refused with a toast
+- [ ] Split: the click snaps to the nearest wall, so it works on non-grid-aligned rooms
+      (imported/legacy polygons), not only on rooms drawn on the current grid [auto]
+- [ ] Split: a click far from any wall (middle of the room) is a miss with a toast —
+      the wall-snap pull is capped, accidental clicks do not pick a wall [auto]
 - [ ] Esc / Ctrl+Z removes the last dot (and its line); Reset clears the path
 - [ ] Closing the contour (click the first dot, ≥4 points) opens the room dialog
 - [ ] Room dialog: area list shows only unassigned areas; picking an area prefills the name
@@ -170,6 +174,16 @@ Run the *core flows* (marked ★ below) in each environment at least once per mi
 
 ## Last self-run
 
+**v1.21.1 (2026-07-16), full audit of v1.16–v1.21.** All `[auto]` items pass (73 frontend
+tests, 12 backend). New smokes on the synthetic home: `smoke_merge_split` (merge fuses
+adjacent rooms keeping the survivor's id; non-adjacent refused with a toast; split creates
+the new room, cancel keeps the room whole, along-wall cut refused) and `smoke_split_nonsnap`.
+Finding turned into a fix (shipped this release): **Split required the click to land on a grid
+node**, so it silently failed on rooms whose walls are not grid-aligned (imported/legacy
+polygons) — the click now snaps to the nearest wall instead of the grid, and `splitRoom()`
+still rejects a bad cut. README (en+ru) gained the merge/split/ruler/scale documentation it
+was missing. The earlier self-run record follows.
+
 **v1.14.0 (2026-07-06), headless demo harness + unit suites.** All `[auto]` items pass
 (43 frontend tests, 11 pure + 12 HA-harness backend tests, `smoke_space_settings`,
 tap/hold/wizard/rules smokes). Bugs found during the run, fixed in the same release: