Add segment length indicators to straight segments in sketch mode (#2935)

* Rough impl of line lengths, still duplicating

* Make sure the labels get cleared along with the rest of the sketch

* Show current units in segment length indicators

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

* Re-run CI after snapshots

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

* Re-run CI

* Make sure `close` segments get insert segment handles

* Skip engine connection tests on Safari with a todo

* Fmt

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

src/clientSideScene/ClientSideSceneComp.tsx

@@ -96,6 +96,7 @@ export const ClientSideScene = ({
     if (!canvasRef.current) return
     const canvas = canvasRef.current
     canvas.appendChild(sceneInfra.renderer.domElement)
+    canvas.appendChild(sceneInfra.labelRenderer.domElement)
     sceneInfra.animate()
     canvas.addEventListener('mousemove', sceneInfra.onMouseMove, false)
     canvas.addEventListener('mousedown', sceneInfra.onMouseDown, false)