refactor(web/m7-377): TrackRow +queue uses Lucide Plus icon + scoped aria-label

web/src/lib/components/TrackRow.svelte

@@ -2,6 +2,7 @@
   import type { TrackRef } from '$lib/api/types';
   import { formatDuration } from '$lib/media/duration';
   import { playQueue, enqueueTrack, playRadio } from '$lib/player/store.svelte';
+  import { Plus } from 'lucide-svelte';
   import LikeButton from './LikeButton.svelte';
   import TrackMenu from './TrackMenu.svelte';
 
@@ -64,10 +65,13 @@
   >📻</button>
   <button
     type="button"
-    aria-label="Add to queue"
+    aria-label={`Add ${track.title} to queue`}
+    title="Add to queue"
     onclick={onAddClick}
     class="rounded p-1 text-text-secondary hover:text-text-primary"
-  >+</button>
+  >
+    <Plus size={16} strokeWidth={1} />
+  </button>
   <TrackMenu {track} />
   <span class="tabular-nums text-text-secondary">{formatDuration(track.duration_sec)}</span>
 </div>