feat: add contact channels (#33308)

apps/meteor/app/apps/server/bridges/livechat.ts

apps/meteor/app/apps/server/converters/visitors.js

apps/meteor/app/livechat/imports/server/rest/sms.ts

apps/meteor/app/livechat/server/api/v1/room.ts

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

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

apps/meteor/server/models/raw/LivechatContacts.ts

apps/meteor/tests/end-to-end/api/livechat/contacts.ts

...ages/apps-engine/src/definition/livechat/ILivechatRoom.ts

packages/core-typings/src/ILivechatContact.ts

packages/core-typings/src/IRoom.ts

packages/model-typings/src/models/ILivechatContactsModel.ts