fix(render): release the atmosphere probe's WebGL context

Lose the throwaway WebGL2 probe context right after the link probe instead
of leaving it for GC; browsers (Safari especially) cap live contexts. Note
that affected devices also lose globe-basemap fog, credit the changelog
entry and move it to the top.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

docs/CURRENT-STATE.md

@@ -701,7 +701,6 @@ snapshots, lifecycle actions and row descriptors. Remount and teardown remove
 listeners and row subscriptions; obsolete completions do not repaint old rows.
 The clear control presents busy state while its existing action owns the transaction.
 
-
 ## Model atmosphere on Apple Metal
 
 Cesium's per-vertex model atmosphere is kept out of the pipeline on devices
@@ -712,13 +711,15 @@ attaches that stage only when `fog.enabled && fog.renderable`, so the viewer
 clears `scene.fog.renderable` and leaves `fog.enabled` — and the fog density
 that drives 3D Tiles screen-space-error scaling — intact. Sky atmosphere and the
 ground-atmosphere fragment path route through locals and are unaffected.
+Affected devices lose distance fog on 3D tiles and on globe basemaps (Esri,
+Bing, keyless), since the globe fog shader uses the same `renderable` flag.
+The probe releases its throwaway WebGL2 context immediately.
 
 Detection is a WebGL2 link probe of the same out-parameter/varying pattern, so a
 future driver fix restores the effect with no code change; iOS/iPadOS platform
 detection is the backstop for when no probe context can be created. Applied
 during viewer construction, before any tile builds a draw command.
 
-
 ## Map Source control ownership
 
 Map Source controls own chip listeners, source-state subscriptions and selection