feat(web): add TrackRow component

Non-interactive album track row with number, title, duration.
Player plan will add click-to-play.

web/src/lib/components/TrackRow.svelte

@@ -0,0 +1,14 @@
+<script lang="ts">
+  import type { TrackRef } from '$lib/api/types';
+  import { formatDuration } from '$lib/media/duration';
+
+  let { track }: { track: TrackRef } = $props();
+</script>
+
+<div class="grid grid-cols-[32px_1fr_auto] items-center gap-4 px-3 py-2 text-sm odd:bg-surface/50">
+  <span class="text-right tabular-nums text-text-secondary">
+    {track.track_number ?? '—'}
+  </span>
+  <span class="truncate">{track.title}</span>
+  <span class="tabular-nums text-text-secondary">{formatDuration(track.duration_sec)}</span>
+</div>

web/src/lib/components/TrackRow.test.ts

@@ -0,0 +1,31 @@
+import { describe, expect, test } from 'vitest';
+import { render, screen } from '@testing-library/svelte';
+import TrackRow from './TrackRow.svelte';
+import type { TrackRef } from '$lib/api/types';
+
+const track: TrackRef = {
+  id: 't1',
+  title: 'So What',
+  album_id: 'xyz',
+  album_title: 'Kind of Blue',
+  artist_id: 'm-davis',
+  artist_name: 'Miles Davis',
+  track_number: 1,
+  disc_number: 1,
+  duration_sec: 545,
+  stream_url: '/api/tracks/t1/stream',
+};
+
+describe('TrackRow', () => {
+  test('renders track number, title, formatted duration', () => {
+    render(TrackRow, { props: { track } });
+    expect(screen.getByText('1')).toBeInTheDocument();
+    expect(screen.getByText('So What')).toBeInTheDocument();
+    expect(screen.getByText('9:05')).toBeInTheDocument();
+  });
+
+  test('track number falls back to dash when missing', () => {
+    render(TrackRow, { props: { track: { ...track, track_number: undefined } } });
+    expect(screen.getByText('—')).toBeInTheDocument();
+  });
+});