gui: Collapse editor lateral panes on switch back to welcome screen
Context
When switching from editor view to welcome screen, editor's lateral panes are not reset, which feels a bit strange when opening a new puzzle.
This MR resets the lateral panes to their initial position (collapsed) on switch from editor view to welcome screen.
What has changed?
Main Changes
gui
- Reset the lateral panes to their initial position (collapsed) on switch from editor view to welcome screen
Others
gui
- Refactored scene switching to be (a bit) more readable
- Reduce controllers visibility to package