Simplify selected card UI

- Remove "Choose a different source" link
- Remove Details toggle
- Simplify meta to just show source (remove length/notes)

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

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

index.html

@@ -1188,7 +1188,6 @@
                         <span id="previewState" class="preview-state">Previewing…</span>
                         <button id="previewStopBtn" type="button" class="linklike" style="display:none;">Stop preview</button>
                     </div>
-                    <button id="chooseDifferentBtn" type="button" class="linklike">Choose a different source</button>
                 </div>
 
                 <div id="iosAudioBanner" class="ios-audio-banner" aria-live="polite">
@@ -1228,10 +1227,6 @@
                     </div>
                 </div>
 
-                <details class="details-toggle" id="detailsToggle">
-                    <summary>Details</summary>
-                    <div id="selectedDetails" class="selected-details"></div>
-                </details>
             </div>
 
         </div>