add: connect to socket by community

direct messages/groups connect by channel id, everything else should connect by channel with the "is_channel" header set to true

crates/core/src/model/channels.rs

@@ -93,7 +93,7 @@ impl Message {
             created: now,
             edited: now,
             content,
-            context: MessageContext::default(),
+            context: MessageContext,
         }
     }
 }