Transform gizmos and bug fixes

1. Transform gizmos (mainly for debug at the moment)
2. Fix getting transforms from layers when scene has been transformed
3. WIP include widgets in canvas bounds
4. GetAllUnselectedActiveWidgets was ignoring non-main canvases
5. Add method for GetLayerByIndex

[CI BUILD]

Assets/Materials/BoundsGhost.mat

@@ -0,0 +1,35 @@
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