Draw the aircraft family, Wildlife Sightings and the Cockpit through the contract

The layers that still had one Cesium and one Navara implementation, or
drew on Cesium only, now draw through engine.movers, engine.lines and
engine.camera on both engines, and application code holds the engine
instead of guessing it from a viewer.

- Aircraft family: flights, military and local ADS-B share one display
  (src/layers/aircraft/render/display.js). The Cesium and Navara
  renderers are gone. Where they differed, the display follows Cesium:
  - attach and visibility tracking, live disableDepthTestDistance
    changes, the tracked glyph's distance scale, model ids that change,
    local ADS-B markers hidden until shown and its UAT ring as a point;
  - the trail head's hidden alpha is 0.45, the contract's
    depthFailAlpha scaled by the head's 0.9.
  The tracked glyph stays over the fleet, as on Navara. The movers
  contract reports readiness per model and reads model axes as the
  glTF's own on every engine. Cesium's follow takes any native target
  through a proxy entity in the ENU frame and mirrors its readout fields.
- Wildlife Sightings draws badges and the density glow as sprite sets
  and its privacy cells as line outlines (no fill yet). It takes clicks
  from engine.input and its card anchors to the engine's canvas and
  camera, so the layer is in both engines' catalogs again and a switch
  keeps the session's layer set.
- Cockpit: cockpitHost takes the engine only. The ridden aircraft is the
  engine follow's target, hidden through its sprite; only the Cesium
  Viewer's stock double-click is still routed around.
- About forty camera, navigation, share-link, HUD, voice, detection and
  layer-lifecycle callers take the engine. isGlobeEngine and
  engineFromViewer calls outside src/globe fall from 51 to 14.

The coupling baseline drops accordingly: layer renderer lines from
5239/12331 to 4546/11106 (Cesium/Navara), `viewer` lines from 2424 to
2209, Cesium-importing files from 69 to 66.

docs/CURRENT-STATE.md

@@ -206,9 +206,13 @@ one application, and only the globe-bound parts move to the next engine.
   (`scripts/qa-strict-parked-release.mjs`).
 - **Renderers per engine.** Each layer keeps its model and display policy in
   engine-neutral files and draws through `render/cesium*.js` or
-  `render/navara*.js`. Cesium renderers are listed in
-  `src/app/layers/renderers.js` (`CESIUM_LAYER_RENDERERS`), Navara ones are
-  loaded by `registerNavaraLayerRenderers` in `src/app/navaraMode.js`. Navara
+  `render/navara*.js`, or through one `render/display.js` that runs on every
+  engine over the globe contract: the aircraft family (flights, military and
+  local ADS-B) draws through `src/layers/aircraft/render/display.js`. Cesium
+  renderers are listed in `src/app/layers/renderers.js`
+  (`CESIUM_LAYER_RENDERERS`), Navara ones are loaded by
+  `registerNavaraLayerRenderers` in `src/app/navaraMode.js`; both register the
+  same display factory for a layer that has one. Navara
   ground effects (heat, pulses, trails, pads, drapes) are declared with
   `defineGroundEffect` (`src/layers/shared/render/navaraGroundEffect.js`);
   their insert order is pinned by `navaraGroundOrder.test.mjs`.
@@ -288,17 +292,23 @@ snapshot, including one whose rows all fall outside coverage or the species
 checks, is a fresh success that clears earlier rows; only a malformed or failed
 upstream reply serves stale and starts a retry cooldown. WHALES accepts only
 recognized cetaceans; other identified marine mammals appear under ALL or
-MAMMALS. Sensitive iNaturalist locations remain 0.2° privacy cells; Acartia
+MAMMALS. Sensitive iNaturalist locations remain 0.2° privacy cells, drawn as
+outlines (`engine.lines`), with no fill yet; Acartia
 positions are rounded to 0.01° on the server. Acartia comments are never retained.
 Observer identity is retained only for photo attribution.
 
-`/api/inaturalist/grid` supplies a dedicated, nonpickable billboard density glow,
+The layer draws on both engines through one display
+(`src/layers/wildlifeSightings/display.js`): taxon badges and the density glow
+are `engine.movers` sprite sets.
+
+`/api/inaturalist/grid` supplies a dedicated, nonpickable sprite density glow,
 with a view-relative density ramp from cool teal to warm amber. Overlapping
 Gaussian splats span four logical cell widths; mono and CRT styles follow map
 and cockpit vision changes. Empty snapshots paint nothing. Full footprints
 stay inside the globe limb with a 5% radius margin; opacity fades from full at
-3,000 km to zero at 8,000 km camera altitude. Culling and cached coordinates
-add no per-frame work and leave sighting counts intact.
+3,000 km to zero at 8,000 km camera altitude. Splats are sized in metres on
+the CPU, only on frames where the camera moved; culling and cached coordinates
+leave sighting counts intact.
 
 Only real sampled observation rows produce taxon badges at their public
 positions. The badges use 28 px screen buckets, a 22 px overlap check and a