feat: daybreak finale turns the contact arrival into a sunrise with a dawn chord

tests/unit/sun-arrival.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest';
 import { SceneResourceBag } from '@/scene/resources';
-import { createSun } from '@/scene/world/sun';
+import { createSun, DAWN_LIFT } from '@/scene/world/sun';
 import { createMutableChapterPalette } from '@/scene/world/palette';
 
 interface Halo {
@@ -107,6 +107,39 @@ describe('destination sun', () => {
     resources.dispose();
   });
 
+  it('lifts the disc, widens the halo and fades the meteors as the dawn rises, without allocating', () => {
+    const resources = new SceneResourceBag();
+    const sun = createSun(resources);
+    const palette = createMutableChapterPalette('destination');
+    const disc = sun.group.getObjectByName('horizon-sun') as unknown as {
+      position: { y: number };
+      material: { uniforms: Record<string, { value: number }> };
+    };
+    const limb = sun.group.getObjectByName('sun-limb-glow') as unknown as { position: { y: number } };
+    const halo = sun.group.getObjectByName('horizon-halo') as unknown as Halo & { position: { y: number } };
+    const meteors = sun.group.getObjectByName('arrival-meteors') as unknown as {
+      material: { uniforms: { uFade: { value: number } } };
+    };
+    sun.update(palette, 1, 10, 0, true, 0);
+    sun.update(palette, 1, 20, 0, true, 0);
+    const night = { y: disc.position.y, width: halo.scale.x };
+    expect(meteors.material.uniforms.uFade.value).toBe(1);
+    const allocation = resources.snapshot();
+
+    sun.update(palette, 1, 20, 0, true, 0.7);
+    expect(meteors.material.uniforms.uFade.value).toBe(1);
+    sun.update(palette, 1, 20, 0, true, 1);
+    expect(disc.position.y).toBeCloseTo(night.y + DAWN_LIFT);
+    expect(DAWN_LIFT).toBe(58);
+    expect(limb.position.y).toBe(disc.position.y);
+    expect(halo.position.y).toBe(disc.position.y);
+    expect(halo.scale.x / night.width).toBeCloseTo(1.18);
+    expect(disc.material.uniforms.uDawn!.value).toBe(1);
+    expect(meteors.material.uniforms.uFade.value).toBe(0);
+    expect(resources.snapshot()).toEqual(allocation);
+    resources.dispose();
+  });
+
   it('does not pulse from route progress alone and cancels when leaving Contact', () => {
     const resources = new SceneResourceBag();
     const sun = createSun(resources);