Keep tracked-entity state in Core records instead of on Cesium entities

Flights, military, satellites, installations, local ADS-B and ALPR hung
gevTrackedId, gevDisplayPosition, gevVisualPosition, gevSelectionOrigin and
gevLabelModel on the Cesium entities they draw, and the tracked readout,
follow camera, cockpit, share links and awareness read them back. They now
live in src/data/entityRecords.js, a Core-owned record per entity: layers
write entityRecord(entity), readers use readEntityRecord(entity). Nothing
changes on screen. This is the first slice of the renderer plan's state
mirror (P1).

The module is exported as ./data/entity-records so hosted code can read the
same records, and window.__godsEyeView.entityRecords gives the QA scripts
the same access from the page.

src/cockpitMath.test.mjs

@@ -365,7 +365,7 @@ test('tracked-identity resolution falls back to layer precedence', () => {
   const civilian = { icao24: 'aaa077' };
   const military = { icao24: 'ae01ce' };
   // No stamped identity (or one that matches neither layer) keeps the historic
-  // civilian-first order so tracking paths without gevTrackedId still work.
+  // civilian-first order so tracking paths without an entity record trackedId still work.
   assert.equal(resolveTrackedAircraftInfo({ civilian, military }).layerId, 'flights');
   assert.equal(
     resolveTrackedAircraftInfo({ civilian, military, trackedId: 'satellites:25544' }).layerId,