Check whether users are in a group

When only membership is needed, call getUsersInGroup() without retrieving complete member profiles.

final presentUserIDs = await OpenIM.iMManager.groupManager.getUsersInGroup(
  groupID,
  userIDList,
);

The first parameter is the target groupID; the second is the list of user IDs to check. A successful Future returns the user IDs actually present in the group.

This query does not trigger member events or return in-group nicknames, roles, or mute state. Use getGroupMembersInfo() when those fields are required.