test(openings): link centered symbol smokes

Issue: #242
User-Visible: no

demo/smoke_isometric_contract.mjs

@@ -30,10 +30,34 @@ const out = await page.evaluate(async () => {
   configSpace.partitions = [{
     id: 'iso-smoke-wall', a: [0.15, 0.12], b: [0.85, 0.12], cm: 15,
   }];
+  configSpace.openings = [
+    { id: 'iso-centred-door', type: 'door', x: 0.325, y: 0.12, angle: 0, length: 0.08,
+      host: { kind: 'partition', id: 'iso-smoke-wall', t: 0.25 } },
+    { id: 'iso-flipped-window', type: 'window', x: 0.5, y: 0.12, angle: 0, length: 0.08,
+      flip_v: true, host: { kind: 'partition', id: 'iso-smoke-wall', t: 0.5 } },
+    { id: 'iso-centred-gate', type: 'gate', x: 0.675, y: 0.12, angle: 0, length: 0.08,
+      flip_v: true, host: { kind: 'partition', id: 'iso-smoke-wall', t: 0.75 } },
+  ];
   card._cfgEpoch++;
   card.requestUpdate();
   await card.updateComplete;
   await enable();
+  const openingBases = card._isoSource()?.build().openings || [];
+  const basis = (id) => openingBases.find((opening) => opening.id === id);
+  const centredDoor = basis('iso-centred-door');
+  const flippedWindow = basis('iso-flipped-window');
+  const centredGate = basis('iso-centred-gate');
+  const wallAxisY = 0.12 * 1000;
+  const halfDepth = (15 / card._cellCm) * card._gridPitch / 2;
+  result.isoOpeningDefaultCentred = centredDoor?.leaves.length === 1
+    && centredDoor.leaves.every((leaf) => Math.abs(leaf.hinge[1] - wallAxisY) < 1e-6);
+  result.isoWindowFlipUsesCanonicalEdge = flippedWindow?.leaves.length === 2
+    && flippedWindow.leaves.every(
+      (leaf) => Math.abs(leaf.hinge[1] - wallAxisY - halfDepth) < 1e-6,
+    );
+  result.isoGateFlipKeepsCentredOrigin = centredGate?.leaves.length === 2
+    && centredGate.leaves.every((leaf) => Math.abs(leaf.hinge[1] - wallAxisY) < 1e-6)
+    && centredGate.leaves.every((leaf) => Math.abs(leaf.turnDeg) === 10);
   const toggle = root().querySelector('[data-hp="projection-toggle"]');
   result.labsSnapshotFrozen = Object.isFrozen(window.__hpLabs)
     && JSON.stringify(window.__hpLabs) === '["iso"]';

scripts/smoke-links.mjs

@@ -27,6 +27,15 @@
 
 /** @type {SmokeLink[]} */
 export const SMOKE_LINKS = [
+  {
+    // #242: pure placement is called inside shared SVG/Iso renderers, while
+    // browser smokes can only inspect the resulting transforms and bases.
+    symbols: ['openingSymbolOffset'],
+    smokes: ['smoke_isometric_contract.mjs', 'smoke_wall_thickness.mjs'],
+    because: 'wall-thickness smoke proves the default and saved-flip SVG translations; '
+      + 'isometric smoke inspects door/window/gate bases from the same helper, but neither '
+      + 'browser bundle exposes the helper name in its test steps',
+  },
   {
     // #234: единый резолвер толщины отрезка цепочки. Смок перехода между
     // толщинами не называет ни `chainSegmentCms`, ни `_draftSegmentCms` — он