Fix cursorShape not updating for messages

Should fix #166 (closed). In my tests, this hasn't broken any existing functionality, but review and further testing from those more familiar with the codebase would be greatly appreciated!

This fix moves the MouseArea that is used to display message information when right clicking or long pressing on it, into the innerObject which contains the TextDelegate for the message itself and the ReactionDelegate for displaying reactions (I think 😅). By making this the first element in the list, the functionality of the MouseArea is kept while allowing the cursorShape property from the TextDelegate for the message to properly change the cursor shape.