[dev-x64]

Adds shareable playlist snapshots that recipients can view and download as CSV without signing in to Spotify.

• Adds a Share action for playlists and Liked Songs, with link copying and a manual-copy fallback.
• Stores the complete snapshot in the URL fragment, keeping sharing entirely client-side.
• Uses DEFLATE with a compact format: shared dictionaries for artist/album names, grouped field columns and abbreviated Spotify URI prefixes.
• Automatically selects whichever representation produces the shorter link.
• Preserves track order, duplicates, Unicode and local tracks, with support for existing version 1 links.
• Excludes access tokens and account metadata, and explains that anyone with the link can view the snapshot.
• Validates incoming data and limits decompression and dictionary expansion.

Validation:

• All 335 Vitest tests and 7 smoke tests pass.
• ESLint, TypeScript, production build and asset smoke check pass.
• Covers 1,000- and 2,000-track round trips, both link formats and CSV downloads.
• The 2,000-track synthetic sample shrank from approximately 86,000 to 79,000 characters.

Limitation: large snapshots still produce long URLs that some messaging apps may truncate. The interface explains this and offers CSV export as a fallback.