[StreamChatPersistence] Add initial implementation

Signed-off-by: Sahil Kumar <[email protected]>

packages/stream_chat_persistence/lib/src/mapper/event_mapper.dart

@@ -0,0 +1,15 @@
+import 'package:stream_chat/stream_chat.dart';
+import 'user_mapper.dart';
+import 'package:stream_chat_persistence/src/db/moor_chat_database.dart';
+
+///
+extension ConnectionEventX on ConnectionEventEntity {
+  ///
+  Event toEvent({User user}) {
+    return Event(
+      me: user,
+      totalUnreadCount: totalUnreadCount,
+      unreadChannels: unreadChannels,
+    );
+  }
+}