fix: smooth scrubber end seeking (#386)

* fix: smooth scrubber end seeking

* fix: stop timeline auto-scroll in fit mode

* feat: use percentage-based timeline zoom

* fix: sync timeline playhead on zoom changes

* fix: reset timeline scroll when returning to fit

* fix: keep timeline controls pinned

packages/studio/src/player/components/PlayerControls.test.ts

@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+import { resolveSeekPercent } from "./PlayerControls";
+
+describe("resolveSeekPercent", () => {
+  it("returns 0 when the track width is invalid", () => {
+    expect(resolveSeekPercent(100, 0, 0)).toBe(0);
+  });
+
+  it("snaps to the start within the edge threshold", () => {
+    expect(resolveSeekPercent(105, 100, 200)).toBe(0);
+  });
+
+  it("snaps to the end within the edge threshold", () => {
+    expect(resolveSeekPercent(298, 100, 200)).toBe(1);
+  });
+
+  it("preserves the true percent away from the edges", () => {
+    expect(resolveSeekPercent(150, 100, 200)).toBe(0.25);
+  });
+});