feat: implemented track level automation

src/util/trackAutomationUtil.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from 'vitest';
+import { KGTrackAutomationPoint } from '../core/track/KGTrackAutomationPoint';
+import {
+  bakeTrackAutomationPointsInWindow,
+  normalizeTrackAutomationPoints,
+  resolveTrackAutomationValueAtBeat,
+} from './trackAutomationUtil';
+
+describe('trackAutomationUtil', () => {
+  it('dedupes same-beat points and keeps the latest value', () => {
+    const normalized = normalizeTrackAutomationPoints([
+      { beat: 1, value: -6 },
+      { beat: 1, value: -3 },
+      { beat: 2, value: 1 },
+    ], 'volume');
+
+    expect(normalized).toEqual([
+      { beat: 1, value: -3 },
+      { beat: 2, value: 1 },
+    ]);
+  });
+
+  it('interpolates between points and falls back to the default before the first point', () => {
+    const points = [
+      new KGTrackAutomationPoint('point-1', 1, -6),
+      new KGTrackAutomationPoint('point-2', 3, 6),
+    ];
+
+    expect(resolveTrackAutomationValueAtBeat(points, 'volume', 0.5, 0)).toBe(0);
+    expect(resolveTrackAutomationValueAtBeat(points, 'volume', 2, 0)).toBe(0);
+  });
+
+  it('bakes intermediate points for changing automation spans', () => {
+    const baked = bakeTrackAutomationPointsInWindow([
+      { beat: 0, value: 0 },
+      { beat: 2, value: 1 },
+    ], 'pan', 0, 2, 250, 120);
+
+    expect(baked[0]).toEqual({ beat: 0, value: 0 });
+    expect(baked.some(point => point.beat > 0 && point.beat < 2)).toBe(true);
+  });
+});