Refine shell status controls and glass rendering; defer cursor redraw safely

shell/ferese-shell/assets/icons/status/brightness.svg

@@ -0,0 +1,4 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.8" stroke-linecap="round" stroke-linejoin="round">
+  <circle cx="12" cy="12" r="4"/>
+  <path d="M12 2v2m0 16v2M2 12h2m16 0h2M5 5l1.4 1.4m11.2 11.2L19 19M19 5l-1.4 1.4M6.4 17.6 5 19"/>
+</svg>