Stately Studio minor improvements

In the last week, we made the following bug fixes and improvements.

Bug fixes

• Live simulation mode is now stopped when you switch machines.
• The child state of a new parallel state will no longer be marked as the initial state.

Improvements

• The editor menu is now available when in version view mode.
• Meta values now support multi-line text input.
• Improved the layout of the starter machine at state.new.
• Improved accessibility of the left drawer toggle.
• Improved accessibility of the Discovery search and filters.
• A variety of internal fixes and improvements.