fix: address GNSS integrity and aircraft emergency review findings

src/data/aircraftRecession.test.mjs

@@ -142,3 +142,15 @@ test('ambient model presentation receives composed alpha without changing blend
   assert.equal(model.colorBlendAmount, 0.9);
   assert.equal(applyAircraftModelTreatment({ model, baseColor: color, alpha: 0.2, params }), 0);
 });
+
+
+test('model hue changes at constant alpha, then clears without redundant writes', () => {
+  const color = (red,green,blue) => ({red,green,blue,withAlpha(alpha){return {red,green,blue,alpha};}});
+  const model = {color:color(1,1,1).withAlpha(0.65)};
+  assert.equal(applyAircraftModelTreatment({model,baseColor:color(1,0.2,0.2),alpha:0.65}),1);
+  assert.equal(model.color.green,0.2);
+  assert.equal(model.color.alpha,0.65);
+  assert.equal(applyAircraftModelTreatment({model,baseColor:color(1,0.2,0.2),alpha:0.65}),0);
+  assert.equal(applyAircraftModelTreatment({model,baseColor:color(1,1,1),alpha:0.65}),1);
+  assert.equal(model.color.green,1);
+});