feat v1.34.0: island rooms — nested contours with evenodd holes

- roomsOverlap: full nesting is legal (islands), edge crossings and
  partial overlaps still rejected; polyContainsPoly + islandsOf pure
  helpers (+2 unit tests, 94 total)
- draw tool: per-click point-in-room rejection removed, validation at
  contour closing; parent rooms with islands render as evenodd paths
  (ring fills correctly, island stays clickable through the hole)
- smoke_island_rooms.mjs; smoke_merge_split stale room-count asserts
  fixed (rg pushed a 5th room; cancelWhole silently false for ages)
- TESTING/CHANGELOG same-commit

docs/CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## v1.34.0 — 2026-07-22 (island rooms)
+- **Nested rooms are now legal**: draw a contour fully inside an existing room
+  (or around one) — a column in a ring-shaped room, an inner room, a wardrobe
+  island. The parent room's fill is rendered with an evenodd hole, so a ring
+  paints as a ring; the island itself stays clickable and can carry its own
+  area, fill and devices. Partial overlaps and duplicate outlines are still
+  rejected (`roomsOverlap` reworked; `polyContainsPoly`/`islandsOf` helpers,
+  unit-tested). The per-click "point inside a room" rejection is gone —
+  validation happens once, when the outline closes.
+
 ## v1.33.5 — 2026-07-22
 - Editor tabs got extended tooltips explaining what each editor is for (plan
   geometry vs device icons vs visual decor).