perf/fix v1.43.1: external audit P1 — render cost, drag threshold, geometry, backend

L1: memoized space model + open pairs (structural fingerprint key, epoch
bumped synchronously at mutation time, not inside the debounce); hoisted
per-room geometry out of the render loop; smoke asserts zero recomputation
across state pushes.

L4: openings get the 3 px drag threshold used by every other pipeline and
only write when the geometry actually changed — taps open the dialog again.

G2: interiorPoint() replaces the vertex mean, so island rooms inside
concave (U/L) parents are accepted and their evenodd holes render; traced
duplicates still are not containment.

G3: segKey rounds before ordering — one shared wall, one key.

B2: _check_write fails closed when the entry is unavailable.
B3: layout/set honours expected_rev and returns the new rev.
B4: config/set without expected_rev over a non-empty store logs a warning.
B5: coordinates reject NaN/Infinity; spaces/rooms/markers/decor/layout capped.

+2 unit tests (118), +2 backend tests (14), smoke_render_perf; docs
same-commit

demo/smoke_render_perf.mjs

@@ -0,0 +1,36 @@
+import { launch } from './serve.mjs';
+const { page, browser } = await launch();
+const res = await page.evaluate(async () => {
+  const out = {};
+  const c = window.__card;
+  // счётчики вызовов тяжёлой геометрии
+  let pairsCalls = 0, buildCalls = 0;
+  const origPairs = c._computeOpenPairs.bind(c);
+  c._computeOpenPairs = (...a) => { pairsCalls++; return origPairs(...a); };
+  const origBuild = c._buildModel.bind(c);
+  c._buildModel = (...a) => { buildCalls++; return origBuild(...a); };
+  // открыть границу, чтобы pairs было что считать
+  const sp = c._curSpaceCfg;
+  const r1 = sp.rooms[0], r2 = sp.rooms[1];
+  r1.open_to = [r2.id]; r2.open_to = [r1.id];
+  c._saveConfig(); c.requestUpdate(); await c.updateComplete;
+  pairsCalls = 0; buildCalls = 0;
+  // 10 «пушей состояния» от HA без изменения конфига
+  for (let i = 0; i < 10; i++) {
+    c.hass = { ...c.hass, states: { ...c.hass.states } };
+    await c.updateComplete;
+  }
+  out.pairsPerRender = pairsCalls;      // должно быть 0: кэш живёт между рендерами
+  out.modelBuildsPer10Renders = buildCalls;
+  // правка конфига обязана инвалидировать кэш
+  const before = pairsCalls;
+  const r3 = sp.rooms[2] || sp.rooms[0];
+  r3.open_to = [r1.id]; r1.open_to = [r2.id, r3.id];
+  c._saveConfig(); c.requestUpdate(); await c.updateComplete;
+  out.invalidatesOnEdit = pairsCalls > before;
+  // геометрия по-прежнему правильная: пунктир на месте
+  out.dashesStillRendered = (c.shadowRoot || c.renderRoot).querySelectorAll('.openwall').length > 0;
+  return out;
+});
+console.log(JSON.stringify(res, null, 1));
+await browser.close();