chore: remove MP3 download UI

Remove the Download MP3 button and all related client-side export logic.

Made-with: Cursor

index.html

@@ -1222,7 +1222,6 @@
                     <div style="margin-top: 14px; display: flex; gap: 12px; flex-wrap: wrap;">
                         <button id="copyLinkBtn" type="button" disabled>Copy link</button>
                         <button id="shareToXBtn" type="button" disabled>Share to X</button>
-                        <button id="downloadMp3Btn" type="button" disabled>Download MP3</button>
                     </div>
                     <div id="shareFallback" style="display: none; margin-top: 12px;">
                         <p style="font-size: 8px; margin: 0 0 8px 0; color: var(--gb-light);">Sorry, copy doesn't work on your device. Here's the link:</p>
@@ -1247,9 +1246,6 @@
                     <strong>How it works:</strong> The Wario Synthesis Engine analyses MIDI files to identify melody, bass, and chord tracks. It then resynthesises each part using Web Audio oscillators tuned to mimic the Game Boy's 4-channel sound chip: two pulse wave channels, one wave channel, and one noise channel. All processing runs client-side in your browser - no server-side audio generation. Built with TypeScript, Vite, and Claude Code.
                 </div>
                 <div class="version-divider"></div>
-                <div class="version-item">
-                    <strong>v1.5</strong> - Download MP3 button, offline rendering for faster exports
-                </div>
                 <div class="version-item">
                     <strong>v1.4</strong> - 16-bit to 8-bit audio fixes, improved synthesis quality
                 </div>