If the user's name consists of just a single word, then use up to two
letters from that word as the placeholder.
This provides better differentiation of users than the current practice
of using just a single letter for everyone.
* refactor most of the components to outside of their Session folder
* finish moving overlay and memberListItem to react hook
* fix bug with kicked member len >2 not being displayed
also sort admins first in UpdateGroupMembers dialog
* fix admin leaving text of groupNotification
* add a useFocusMount hook to focus input fields on mount
* make click avatar convo item open only user dialog
* cleanup config default.json
* make sure to use convoController to build sync message
* disable showing pubkey on opengroups
* add a pause on audio playback
Fixes#2079
William Grant
Audric Ackermann
Ian Macdonald