test(qa): flights parity checklist on both engines, side by side

Task 10b:
- qa-w1-layers (flights): 3 focus (the selected object is the focus target,
  at the followed centre ≤ 3 px), 4 tracking (held ≤ 3 px for 5 s; wheeled
  in, ≥ 149 m), 5 the layer's queries (tracked info, contacts, nearby,
  detectable; compared by --compare), 6 share links (the followed object
  restored on the same and on the other engine). Clicks only on points the
  canvas takes (the Navara attribution card covered the old empty point).
  --compare reports the global pose's 2.3 px as the cameras' (Cesium
  projects its own nadir 2.27 px off centre at 15,000 km).
  Cesium 19/19, Navara 20/20, parity.
- qa-flights-engines (new): the same frozen synthetic fleet at the global,
  city, orbit and near (JFK, oblique) poses on both engines, UI hidden;
  side-by-side JPEGs (docs/migration/phase3/flights, models off and on),
  the same objects in the frame, screen points ≤ 2 px, glyph fill colours
  (brightest pixel at the glyph) within 3. 12/12 with models off and on.
- qa-labels: on an engine with flights but not military/satellites, the
  deterministic 12,000 / 5,200 field is all aircraft, so detection is
  gated on Navara too: 14/14 (Cesium 14/14 unchanged).

scripts/format-scope.json

@@ -1118,6 +1118,7 @@
   "src/app/layers/qaSources.js",
   "src/app/layers/qaSources.test.mjs",
   "scripts/qa-w1-layers.mjs",
+  "scripts/qa-flights-engines.mjs",
   "src/bench/w1Feeds.js",
   "scripts/qa-map-switch.mjs",
   "scripts/qa-engine-notice.mjs"