feat: add personal playlists and shareable track links

EOF

Co-authored-by: Cursor <cursoragent@cursor.com>

packages/core/src/share.test.ts

@@ -0,0 +1,9 @@
+import { describe, expect, it } from 'vitest';
+
+import { trackShareUrl } from './share';
+
+describe('trackShareUrl', () => {
+  it('builds a page URL without stream credentials', () => {
+    expect(trackShareUrl('https://music.example', 'ab/cd')).toBe('https://music.example/track/ab%2Fcd');
+  });
+});