Tweak the editor CheckButton "presed" appearance to be more recognizable

The blue accent color is now used, which matches the default editor
accent color.

It doesn't change to match the currently configured accent color
automatically, but doing so would require modifying the CheckButton
class a lot for little benefit.

editor/icons/GuiToggleOn.svg

@@ -1 +1 @@
-<svg height="16" viewBox="0 0 38 15.999999" width="38" xmlns="http://www.w3.org/2000/svg"><path d="m8 1c-3.878 0-7 3.122-7 7s3.122 7 7 7h22c3.878 0 7-3.122 7-7s-3.122-7-7-7zm22 2a5 5 0 0 1 5 5 5 5 0 0 1 -5 5 5 5 0 0 1 -5-5 5 5 0 0 1 5-5z" fill="#e0e0e0" stroke-width="55.8958"/></svg>
+<svg height="16" viewBox="0 0 38 15.999999" width="38" xmlns="http://www.w3.org/2000/svg"><path d="m8 1c-4 0-7 3.0000002-7 7.0000002 0 3.9999998 3 6.9999998 7 6.9999998h22c4 0 7-3 7-6.9999998 0-4-3-7.0000002-7-7.0000002-7.333334 0-14.55609 0-22 0z" fill="#699ce8"/><circle cx="30" cy="8" fill="#fefefe" r="5"/></svg>

editor/icons/GuiToggleOnMirrored.svg

@@ -1 +1 @@
-<svg xmlns="http://www.w3.org/2000/svg" width="42" height="26"><path fill="#e0e0e0" d="M31 5c4.986 0 9 3.568 9 8s-4.014 8-9 8H11c-4.986 0-9-3.568-9-8s4.014-8 9-8zM10 8a-5 5 0 0 0-5 5-5 5 0 0 0 5 5-5 5 0 0 0 5-5-5 5 0 0 0-5-5z"/></svg>
+<svg height="26" width="42" xmlns="http://www.w3.org/2000/svg"><path d="m31 5c4.986 0 9 3.568 9 8s-4.014 8-9 8h-20c-4.986 0-9-3.568-9-8s4.014-8 9-8z" fill="#699ce8"/><circle cx="10" cy="13" fill="#fefefe" r="5"/></svg>