style(immersive): increase artwork size and reduce wasted padding

Bump artwork vh constraint from 60vh to 72vh — the previous value was
the bottleneck on laptop screens (461px on 768px viewport). Now yields
~553px. Reduce vertical padding from 164px to 140px total. Compact
track info margins below artwork.

cc

src/lib/components/immersive/ImmersiveArtwork.svelte

@@ -36,7 +36,7 @@
   /* Floating variant (default) */
   .artwork-wrapper {
     width: 100%;
-    max-width: min(42vw, 60vh);
+    max-width: min(42vw, 72vh);
     aspect-ratio: 1;
     border-radius: 12px;
     overflow: hidden;
@@ -55,7 +55,7 @@
   .vinyl-disc {
     position: relative;
     width: 100%;
-    max-width: min(42vw, 60vh);
+    max-width: min(42vw, 72vh);
     aspect-ratio: 1;
     border-radius: 50%;
     background: linear-gradient(
@@ -104,14 +104,14 @@
   @media (max-width: 1200px) {
     .artwork-wrapper,
     .vinyl-disc {
-      max-width: min(38vw, 52vh);
+      max-width: min(40vw, 65vh);
     }
   }
 
   @media (max-width: 900px) {
     .artwork-wrapper,
     .vinyl-disc {
-      max-width: min(55vw, 32vh);
+      max-width: min(55vw, 35vh);
     }
   }
 </style>

src/lib/components/immersive/ImmersivePlayer.svelte

@@ -892,7 +892,7 @@
     display: flex;
     align-items: center;
     justify-content: center;
-    padding: 64px 40px 100px;
+    padding: 52px 40px 88px;
     gap: 40px;
     z-index: 1;
   }
@@ -956,7 +956,7 @@
   .split-track-album {
     font-size: clamp(12px, 1.5vw, 14px);
     color: var(--alpha-50, rgba(255, 255, 255, 0.5));
-    margin: 0 0 12px 0;
+    margin: 0 0 6px 0;
     white-space: nowrap;
     overflow: hidden;
     text-overflow: ellipsis;
@@ -965,7 +965,7 @@
   .split-quality-badge {
     display: flex;
     justify-content: center;
-    margin-top: 8px;
+    margin-top: 4px;
   }
 
   .panel-section {