add setting for primary channel

src/ViewModel/chatListViewModel.tsx

@@ -32,6 +32,12 @@ export default class ChatListViewModel {
     return this.sortedPrimaryChannels.indexOf(chat.primaryChannel.value);
   }
 
+  updateIndices = (): void => {
+    for (const chatViewModel of this.chatViewModels.value) {
+      chatViewModel.updateIndex();
+    }
+  }
+
   // methods
   createChat = (): void => {
     const chatModel: ChatModel = this.chatListModel.createChat(

src/ViewModel/chatViewModel.tsx

@@ -43,6 +43,12 @@ export default class ChatViewModel {
     this.chatListViewModel.closeChat();
   };
 
+  setPrimaryChannel = (): void => {
+    this.chatModel.setPrimaryChannel(this.primaryChannelInput.value);
+    this.primaryChannel.value = this.chatModel.info.primaryChannel;
+    this.chatListViewModel.updateIndices();
+  }
+
   // restore
   restorePageSelection = (): void => {
     const path: string[] = storageKeys.chatLastUsedPage(this.chatModel.id);