Reject empty recording downloads and store WebM with correct MIME.

Mark legacy zero-byte placeholders as failed, validate files on show/download, and surface upload errors in the meeting room.

Co-authored-by: Cursor <cursoragent@cursor.com>

resources/views/meet/recordings/index.blade.php

@@ -15,7 +15,7 @@
                 </div>
                 <div class="flex gap-2">
                     <a href="{{ route('meet.recordings.show', $recording) }}" class="text-sm text-indigo-600 hover:underline">View</a>
-                    @if ($recording->isReady())
+                    @if ($recording->hasPlayableFile())
                         <a href="{{ route('meet.recordings.download', $recording) }}" class="text-sm text-slate-600 hover:underline">Download</a>
                     @endif
                 </div>

resources/views/meet/recordings/show.blade.php

@@ -70,8 +70,8 @@
                 </div>
             </dl>
 
-            @if ($recording->isReady())
-                <p class="mt-5 text-sm text-slate-600">Your recording is stored on Ladill and ready to download.</p>
+            @if ($recording->hasPlayableFile())
+                <p class="mt-5 text-sm text-slate-600">Stored on Ladill as WebM — VLC, Chrome, and QuickTime can play it after download.</p>
             @elseif ($recording->status === 'processing')
                 <div class="mt-5 flex items-start gap-3 rounded-xl border border-amber-200 bg-amber-50 px-4 py-3">
                     <svg class="mt-0.5 h-5 w-5 shrink-0 animate-spin text-amber-600" fill="none" viewBox="0 0 24 24" aria-hidden="true">
@@ -90,7 +90,7 @@
             @endif
 
             <div class="btn-group mt-6">
-                @if ($recording->isReady())
+                @if ($recording->hasPlayableFile())
                     <a href="{{ route('meet.recordings.download', $recording) }}" class="btn-secondary btn-secondary-sm">
                         <svg class="h-4 w-4" fill="none" stroke="currentColor" stroke-width="1.75" viewBox="0 0 24 24" aria-hidden="true">
                             <path stroke-linecap="round" stroke-linejoin="round" d="M3 16.5v2.25A2.25 2.25 0 0 0 5.25 21h13.5A2.25 2.25 0 0 0 21 18.75V16.5M16.5 12 12 16.5m0 0L7.5 12M12 16.5V3"/>