test(qa): W1 baseline and the main-chunk check

scripts/check-main-chunk.mjs (npm run check:main-chunk) finds the main
chunk of a build (the Vite manifest's entry, or the module script
dist/index.html loads), follows its static imports and fails when any of
them carries three or Navara markers; it prints the sizes. Base build:
main chunk 2,850,229 bytes (gzip 881,783), no static imports, clean.

scripts/qa-w1-baseline.mjs records Cesium mode for the W1 layers (flights,
military, local ADS-B, vessels, satellites, launches): counts, five known
objects with positions and screen points, JPEGs (path, size, sha256) at
the global / New York (JFK) / orbit poses, a tracked object's camera pose
after 2 s and what its share link restores. Live sources until the
fixture sources of Task 8.

package.json

@@ -50,6 +50,7 @@
     "qa:street-level": "node scripts/qa-street-level.mjs",
     "qa:street-level:fixtures": "node scripts/qa-street-level.mjs --fixtures",
     "check:boundaries": "node scripts/check-import-directions.mjs && node scripts/check-package-boundaries.mjs",
+    "check:main-chunk": "node scripts/check-main-chunk.mjs",
     "qa:transit": "node scripts/qa-transit.mjs",
     "mcp": "node server/mcp/stdio.js"
   },