[native] Introduce communityCreationButton to CommunityDrawerContent
Add community creation button to community selection drawer.
Just layout/styling for now, functionality will be added in subsequent diff.
Looks as expected (dark mode):
Looks as expected (light mode):
Reviewers: ashoat, ginsu
Reviewed By: ashoat
Subscribers: ted, tomek
Differential Revision: https://phab.comm.dev/D7924