Building on #2331 which adds the initial support for the new group types in Kafka 4.2 (#2248), we should improve the group page to display configuration that has been set for a group. This would involve two pieces of work. (1) add configs to the Group model, similar to a Topic and (2) update the group details UI to show the current membership/offset information as well as a new configuration tab. The configuration tab could use the same look as the topic configurations.