Add a username to the ChatMember model

Author: madhead

core/src/main/kotlin/me/madhead/tyzenhaus/core/service/GroupMembersService.kt

@@ -29,6 +29,7 @@ class GroupMembersService(
                     id = it.user.id.chatId,
                     firstName = it.user.firstName,
                     lastName = it.user.lastName,
+                    username = it.user.username?.usernameWithoutAt,
                 )
             }
         )

entity/src/main/kotlin/me/madhead/tyzenhaus/entity/group/members/GroupMembers.kt

@@ -10,6 +10,7 @@ data class GroupMember(
     val id: Long,
     val firstName: String,
     val lastName: String,
+    val username: String?,
 )
 
 /**