fix: fix notifications not working for community chats

Fixes #2210

src/app/chat/view.nim

@@ -482,9 +482,11 @@ QtObject:
           msgIndex = self.messageList[msg.chatId].messages.len - 1
       self.messagePushed(msgIndex)
       if self.channelOpenTime.getOrDefault(msg.chatId, high(int64)) < msg.timestamp.parseFloat.fromUnixFloat.toUnix:
-        let channel = self.chats.getChannelById(msg.chatId)
+        var channel = self.chats.getChannelById(msg.chatId)
         if (channel == nil):
-          continue
+          channel = self.communities.getChannel(msg.chatId)
+          if (channel == nil):
+            continue
 
         if msg.chatId == self.activeChannel.id:
           discard self.status.chat.markMessagesSeen(msg.chatId, @[msg.id])

src/app/chat/views/communities.nim

@@ -340,4 +340,12 @@ QtObject:
     except Exception as e:
       error "Error declining request to join the community", msg = e.msg
       return "Error declining request to join the community"
-    return ""
+    return ""
+
+  proc getChannel*(self: CommunitiesView, channelId: string): Chat =
+    for community in self.joinedCommunityList.communities:
+      for chat in community.chats:
+        if (chat.id == channelId):
+          return chat
+      
+