refactor: Feature parity for EE models (#28614)

apps/meteor/app/livechat/server/api/lib/livechat.ts

apps/meteor/ee/app/license/server/getStatistics.ts

...meteor/ee/app/livechat-enterprise/server/api/lib/units.ts

apps/meteor/ee/app/livechat-enterprise/server/lib/units.ts

apps/meteor/ee/app/models/server/models/LivechatUnit.js

...meteor/ee/definition/rest/v1/omnichannel/businessUnits.ts

apps/meteor/ee/server/models/LivechatDepartment.ts

apps/meteor/ee/server/models/LivechatRooms.ts

apps/meteor/ee/server/models/LivechatUnit.ts

apps/meteor/ee/server/models/Messages.ts

apps/meteor/ee/server/models/Users.ts

apps/meteor/ee/server/models/raw/CannedResponse.ts

apps/meteor/ee/server/models/raw/LivechatDepartment.ts

apps/meteor/ee/server/models/raw/LivechatPriority.ts

apps/meteor/ee/server/models/raw/LivechatRooms.ts

apps/meteor/ee/server/models/raw/LivechatTag.ts

apps/meteor/ee/server/models/raw/LivechatUnit.ts

apps/meteor/ee/server/models/raw/LivechatUnitMonitors.ts

apps/meteor/ee/server/models/raw/Messages.ts

apps/meteor/ee/server/models/raw/Users.ts