Save an episode without its dead air when DeadAir is on (#186)

The save button fetched the original while the player played it shortened.
/media/{id}/deadair sends the original's ID3 tag and then the pieces of the
person's plan one after another, read as it goes: MP3 and ADTS frames each
stand alone, so that is a file any player takes, and nothing is stored, as
with the playlist. The tag stops at the first kept frame, since what can
follow it, the Xing frame, gives the original's length.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/src/items.ts

@@ -327,7 +327,9 @@ function encBox(x){
     ? `Delete for everyone (shared with ${f.subscribers-1} other ${f.subscribers===2?'person':'people'} reading this feed)`
     : 'Delete file';
   const delBtn=`<button class="btn ico danger" data-a="del" data-enc="${x.id}" title="${delLabel}" aria-label="${delLabel}">${ICON.trash}</button>`;
-  const saveBtn=`<a class="btn ico" href="/media/${x.id}" download title="Save to this computer" aria-label="Save to this computer">${ICON.save}</a>`;
+  // Played without its dead air, so saved without it too (#186).
+  const saveLabel=x.deadair>0?'Save to this computer, without its dead air':'Save to this computer';
+  const saveBtn=`<a class="btn ico" href="/media/${x.id}${x.deadair>0?'/deadair':''}" download title="${saveLabel}" aria-label="${saveLabel}">${ICON.save}</a>`;
   // The publisher's address, not this server's copy, which only someone signed in here can open.
   const shareBtn=`<button class="btn ico" data-a="share" data-enc="${x.id}" title="Share the file" aria-label="Share the file">${ICON.share}</button>`;
   if(x.path && !isPlayable(x)){