Check that an engine switch draws what a cold start from the share link draws

qa-switch-equals-cold-start switches engines in both directions with each
layer on deterministic fixtures, then opens the share link of the same
state in a new page on the target engine, and compares the draw ledgers
and the probe's view of the layer. It runs as 19 acceptance groups
covering all 38 layers.

State a layer keeps through a switch but the share link does not carry is
declared as sessionState (the directions route, Radio's selected station
and audio state, the wind reading, local ADS-B's and OSM Places' local
toggles and results); a test checks each declaration against what the
layer really retains, so a declaration cannot hide a regression.

scripts/qa-all-layer-switches.mjs

@@ -286,6 +286,125 @@ const soakRuns = quick
 const longRun = quick ? '--swaps=100' : '--swaps=500';
 // label, script, layers, extra arguments, timeout in seconds.
 const runs = [
+  [
+    'switch-equals-cold-start--aircraft',
+    'switch-equals-cold-start',
+    ['flights', 'military'],
+    ['--group=aircraft'],
+  ],
+  [
+    'switch-equals-cold-start--local',
+    'switch-equals-cold-start',
+    ['local-adsb', 'local-dams', 'local-datacenters'],
+    ['--group=local'],
+  ],
+  [
+    'switch-equals-cold-start--ground',
+    'switch-equals-cold-start',
+    ['ais-live-vessels', 'air-quality', 'gnss-integrity', 'fire-perimeters'],
+    ['--group=ground'],
+  ],
+  [
+    'switch-equals-cold-start--contacts',
+    'switch-equals-cold-start',
+    ['military-awareness', 'military-installations'],
+    ['--group=contacts'],
+  ],
+  [
+    'switch-equals-cold-start--open',
+    'switch-equals-cold-start',
+    ['drone-airspace', 'osm-places', 'sea-marks', 'ski-pistes'],
+    ['--group=open'],
+  ],
+  [
+    'switch-equals-cold-start--weather',
+    'switch-equals-cold-start',
+    [
+      'weather-radar',
+      'weather-satellite',
+      'weather-lightning',
+      'weather-cyclones',
+    ],
+    ['--group=weather'],
+  ],
+  [
+    'switch-equals-cold-start--wind',
+    'switch-equals-cold-start',
+    ['wind'],
+    ['--group=wind'],
+  ],
+  [
+    'switch-equals-cold-start--ghostmaps',
+    'switch-equals-cold-start',
+    ['s2-ghostmaps'],
+    ['--group=ghostmaps'],
+  ],
+  [
+    'switch-equals-cold-start--wildlife',
+    'switch-equals-cold-start',
+    ['wildlife-sightings'],
+    ['--group=wildlife'],
+  ],
+  [
+    'switch-equals-cold-start--urban',
+    'switch-equals-cold-start',
+    ['bikeshare', 'transit', 'earthquakes'],
+    ['--group=urban'],
+  ],
+  [
+    'switch-equals-cold-start--cameras',
+    'switch-equals-cold-start',
+    ['cctv', 'alpr-cameras'],
+    ['--group=cameras'],
+  ],
+  [
+    'switch-equals-cold-start--radio',
+    'switch-equals-cold-start',
+    ['radio'],
+    ['--group=radio'],
+  ],
+  [
+    'switch-equals-cold-start--space',
+    'switch-equals-cold-start',
+    ['satellites', 'rocket-launches'],
+    ['--group=space'],
+  ],
+  [
+    'switch-equals-cold-start--traffic',
+    'switch-equals-cold-start',
+    ['traffic'],
+    ['--group=traffic'],
+  ],
+  [
+    'switch-equals-cold-start--street',
+    'switch-equals-cold-start',
+    ['street-level'],
+    ['--group=street'],
+  ],
+  [
+    'switch-equals-cold-start--imagery',
+    'switch-equals-cold-start',
+    ['recent-imagery'],
+    ['--group=imagery'],
+  ],
+  [
+    'switch-equals-cold-start--nepal',
+    'switch-equals-cold-start',
+    ['bhote-koshi-locator', 'bhote-koshi-2026'],
+    ['--group=nepal'],
+  ],
+  [
+    'switch-equals-cold-start--cables',
+    'switch-equals-cold-start',
+    ['telegeography-submarine-cables', 'directions'],
+    ['--group=cables'],
+  ],
+  [
+    'switch-equals-cold-start--fires',
+    'switch-equals-cold-start',
+    ['local-firms'],
+    ['--group=fires'],
+  ],
   ['engine-switch', 'engine-switch', ['earthquakes']],
   ['director-engine-switch', 'director-engine-switch', []],
   ['layer-handoff', 'layer-handoff', ['flights']],