Add a current default unit indicator with menu to switch (#2937)

* Add a units indicator with a menu to switch default units

* Add a playwright test, add a SR label

* A snapshot a day keeps the bugs away! 📷🐛 (OS: ubuntu)

* Re-run CI

* A snapshot a day keeps the bugs away! 📷🐛 (OS: ubuntu)

* Re-run CI

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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

src/components/Gizmo.tsx

@@ -119,7 +119,7 @@ export default function Gizmo() {
       <div
         ref={wrapperRef}
         aria-label="View orientation gizmo"
-        className="grid place-content-center rounded-full overflow-hidden border border-solid border-primary/50 pointer-events-auto"
+        className="grid place-content-center rounded-full overflow-hidden border border-solid border-primary/50 pointer-events-auto bg-chalkboard-10/70 dark:bg-chalkboard-100/80 backdrop-blur-sm"
       >
         <canvas ref={canvasRef} />
         <ContextMenu