room settings button: room-centred, icon-sized, zooms with the plan

Owner's spec: the button is no longer glued to the room NAME (which the user
can drag anywhere) — it anchors to the geometric centre of the ROOM
(interiorPoint for polygons, so an L-shaped room gets a point actually
inside it), one button-height below centre so it never covers the name,
whose default position is that same centre. Height is 70% of a device icon
box, and since --icon-size already rescales with the view, the button zooms
with the plan instead of keeping a constant screen size (verified: x2.2 zoom
-> x2.20 button). The small metric rows under the room name (temperature,
humidity, signal, lights) now render in the plan editor too — they used to
be view-mode only.

smoke_room_cards updated: plainInPlan now asserts metrics ARE present in the
editor (the old assertion pinned the old behaviour), plus gearDetached.

demo/smoke_room_cards.mjs

@@ -36,8 +36,14 @@ const res = await page.evaluate(async () => {
   c._setMode('plan'); await c.updateComplete;
   const planLbl = sr().querySelector('.roomlabel');
   out.handlesInPlan = planLbl?.querySelectorAll('.rlhandle').length === 4;
-  // метрики скрыты в редакторе плана (карточка = имя, чтобы не мешать разметке)
-  out.plainInPlan = sr().querySelectorAll('.roomlabel.card').length === 0;
+  // метрики видны и в редакторе плана (решение владельца, 2026-07-29)
+  out.plainInPlan = sr().querySelectorAll('.roomlabel.card').length > 0;
+  // кнопка настроек — отдельно от подписи, в центре комнаты, с размером от иконки
+  out.gearDetached = (() => {
+    const g = sr().querySelector('.rlgearbtn');
+    if (!g || g.closest('.roomlabel')) return false;
+    return getComputedStyle(g).height !== 'auto';
+  })();
   // масштаб: сымитируем resize через прямой вызов
   const room = c._spaceModel().rooms.find((r) => r.name);
   c._rlResize = { id: 'rl_' + room.id, space: spId, k0: 1, cx: 100, cy: 100, d0: 50 };