fix(fullscreen-player): stop mesh blob and portrait animations in no-compositing mode (#175)

In software compositing (WEBKIT_DISABLE_COMPOSITING_MODE=1), WebKit renders
entirely on the CPU. The mesh blob animations were not covered by the
no-compositing overrides: blob-a occupies 130×130% of the viewport, so each
frame the CPU had to composite a surface larger than the screen. On high-DPI
displays (e.g. 8K) this drops the fullscreen player to ~10 FPS.

- Stop mesh blob pan animations (static gradients are preserved)
- Stop portrait drift animation (filter was already removed)
- Remove box-shadow from the seekbar played bar (its width changes on every
  playback tick; in software mode each change triggers a box-shadow repaint)

src/styles/components.css

@@ -3526,10 +3526,11 @@ html.no-compositing .fs-close {
   background: rgba(0, 0, 0, 0.45);
 }
 
-/* Portrait: remove CSS filter (drop-shadow) and will-change */
+/* Portrait: remove CSS filter (drop-shadow), will-change and drift animation */
 html.no-compositing .fs-portrait {
   filter: none;
   will-change: auto;
+  animation: none;
 }
 
 /* Portrait wrap: replace mask-image fade with a pseudo-element overlay gradient.
@@ -3563,6 +3564,20 @@ html.no-compositing .fs-lyrics-rail {
   will-change: auto;
 }
 
+/* Mesh blobs: stop animations — in software mode each frame composites surfaces
+   larger than the screen (blob-a is 130 × 130 % of the viewport); on high-DPI
+   displays this saturates the CPU and drops the player to ~10 FPS.
+   Static gradients are preserved; only the slow pan animation is removed. */
+html.no-compositing .fs-mesh-blob {
+  animation: none;
+}
+
+/* Seekbar played bar: remove box-shadow — its width changes on every playback
+   tick; in software rendering each change triggers a box-shadow repaint. */
+html.no-compositing .fs-seekbar-played {
+  box-shadow: none;
+}
+
 /* Chat */
 .chat-popup {
   position: absolute;