Replicate a lot of stuff for (threaded) private groups

...arproject/briar/desktop/privategroups/PrivateGroupCard.kt

...ect/briar/desktop/privategroups/PrivateGroupInfoDrawer.kt

...arproject/briar/desktop/privategroups/PrivateGroupItem.kt

...arproject/briar/desktop/privategroups/PrivateGroupList.kt

.../briar/desktop/privategroups/PrivateGroupListViewModel.kt

...project/briar/desktop/privategroups/PrivateGroupScreen.kt

...briar/desktop/privategroups/ThreadedConversationHeader.kt

...t/briar/desktop/privategroups/ThreadedConversationItem.kt

.../desktop/privategroups/ThreadedConversationMessageItem.kt

...briar/desktop/privategroups/ThreadedConversationScreen.kt

...ar/desktop/privategroups/ThreadedConversationViewModel.kt

.../briarproject/briar/desktop/privategroups/ThreadedText.kt

...ain/kotlin/org/briarproject/briar/desktop/ui/Constants.kt

...in/kotlin/org/briarproject/briar/desktop/ui/MainScreen.kt

...g/briarproject/briar/desktop/viewmodel/ViewModelModule.kt