Cut duplicated and dead code across the engines, the layers and the QA scripts

- src/geo drops the ported debug argument checks and the tests that
  bitExact already covers; package boundaries accept a directory entry,
  so src/geo/ is listed once per group.
- Cesium no longer carries movers and lines nobody draws with: they are
  optional engine capabilities. The fake engine and the Cesium camera use
  the shared cameraMath; unused contract tables, clock.ticked, the
  'finest' surface detail and Navara click statistics are gone.
- ALPR keeps one overlay core and one presentation model for both
  engines, bikeshare one station bookkeeping, the Navara ground effects
  one definition helper; image atlases, view centres, mover banks and
  colours are shared.
- The legacy switch route, the clock offset and rate controls and other
  unused exports are removed.
- The acceptance runs the Navara draw, geo import and scope checks;
  scenarios use the harness switch and page helpers; the main chunk
  check keeps the size budget only and runs once in CI.

build/initialChunkGuard.js

@@ -2,8 +2,7 @@
 // initial chunks are every entry chunk and what it imports statically;
 // navaraMode.js reaches Navara only through import(), so three and
 // @navaramap/* belong to lazy chunks. This checks the bundle's module ids
-// (what Rollup put in each chunk), and fails the build otherwise;
-// scripts/check-main-chunk.mjs checks the built files' text as well.
+// (what Rollup put in each chunk), and fails the build otherwise.
 
 /**
  * Module ids that only the Navara engine may load, when no package list is