Measure engine coupling, QA harness use and contract coverage

Counters that may only fall, each with a committed baseline and a test
that fails on growth:

- report-engine-coupling.mjs gains layer modules that take the viewer
  in attachRenderer (33), layer folders with their own "view being
  restored" flag (9), engine.surface calls outside src/globe (41) and
  layer ids named in the engine switch (3).
- report-qa-harness.mjs counts QA scripts that launch Chrome themselves
  (98), wait with fixed sleeps (117), take the hidden loading screen as
  readiness (9), read Cesium-only objects (75) or define their own
  waitFor helpers (19).
- withCallLog records every contract member the contract suite calls on
  the fake engine; contractCoverage.test.mjs fails when a member outside
  contract-uncalled-baseline.json goes uncalled, and when a listed one
  is called now, so the list of 12 only shrinks.

scripts/engineCoupling.test.mjs

@@ -39,3 +39,85 @@ test('a metric that grows is reported, one that falls is not', () => {
     ['viewerLines'],
   );
 });
+
+test('renderer attachment counts definitions once per module, not calls', () => {
+  const { measure } = ENGINE_COUPLING_METRICS.find(
+    ({ id }) => id === 'attachRendererWithViewer',
+  );
+  assert.equal(
+    measure([
+      {
+        text: 'attachRenderer(viewer, options = {}) {}\nattachRenderer(scene) {}',
+      },
+      { text: 'function attachRenderer(\n _viewer, options\n) {}' },
+      { text: 'const attachRenderer = (nextViewer) => {};' },
+      {
+        text: 'attachRenderer(_scene); layer.attachRenderer(viewer, options);',
+      },
+      { text: 'attachRenderer(engine) {}' },
+      { text: 'attachRenderer(viewerState) {}' },
+    ]),
+    3,
+  );
+});
+
+test('restore flags count layer directories and surface calls exclude globe', () => {
+  const measure = (id, files) =>
+    ENGINE_COUPLING_METRICS.find((metric) => metric.id === id).measure(files);
+  assert.equal(
+    measure('restoreFlagCopies', [
+      {
+        file: 'src/layers/traffic/lifecycle.js',
+        text: 'state._restoringViewport = true;',
+      },
+      {
+        file: 'src/layers/traffic/viewport.js',
+        text: 'state._restoringViewport',
+      },
+      { file: 'src/layers/alpr/index.js', text: 'let restoringView = false;' },
+      {
+        file: 'src/layers/streetLevel/index.js',
+        text: 'let waitingForView = false;',
+      },
+      { file: 'src/app/view.js', text: 'let restoringView = false;' },
+    ]),
+    3,
+  );
+  const text = [
+    'terrainHeight',
+    'sampleHeight',
+    'sampleHeightDetailed',
+    'sampleTerrainMostDetailed',
+    'clampToHeight',
+    'raycast',
+  ]
+    .map((name) => `engine.surface.${name}(point);`)
+    .join('\n');
+  assert.equal(
+    measure('surfaceCallsOutsideGlobe', [
+      { file: 'src/globe/navara/surface.js', text },
+      { file: 'src/layers/traffic/viewport.js', text },
+      {
+        file: 'src/app/view.js',
+        text: 'engine.surface?.raycast?.(ray); surface.tilesLoaded();',
+      },
+    ]),
+    7,
+  );
+});
+
+test('engine switch layer ids count lines and follow the catalog', () => {
+  const { measure } = ENGINE_COUPLING_METRICS.find(
+    ({ id }) => id === 'engineSwitchLayerIds',
+  );
+  assert.equal(
+    measure([
+      {
+        file: 'src/standalone/engineSwitch.js',
+        text: "get('directions'); get('satellites');\nget('traffic');\nget('not-a-layer');",
+      },
+      { file: 'src/app/view.js', text: "get('directions');" },
+    ]),
+    2,
+  );
+});