Remove redundant info box from selected card

Consolidated messaging - the chooser helper already explains MIDI selection

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

index.html

@@ -1177,10 +1177,6 @@
                 <h2 id="selectedTitle" class="selected-title">No source selected</h2>
                 <div id="selectedMeta" class="selected-meta">Search for a song, then choose a source to use.</div>
 
-                <!-- selected_pre_generate only -->
-                <div id="selectedExpectation" class="selected-meta" style="margin-top: 8px;">
-                    Some MIDI files work better than others. If the result sounds off, try another source.
-                </div>
 
                 <div class="selected-actions" id="preGenActions">
                     <button id="motifBtn" class="primary" disabled>Generate music</button>