Create a new load carrier.
The identifier field cannot be changed after creation.
Required fields: id, localizedName (with at least one language), isBookable, status.
Optional fields: localizedDescription, preset (dimensions), restrictions.

Restrictions:

• Use restrictions to limit which shippers can select this load carrier in the booking flow.
• Structure: {combinator: 'and'|'or', rules: [{field: string, operator: string, value: string}]}
• Available fields: id, name, status, createdAt, entityInfo.email, entityInfo.country, entityInfo.city, entityInfo.zipCode, source.type
• Example: {combinator: 'and', rules: [{field: 'entityInfo.country', operator: '=', value: 'DEU'}]}
• If no restrictions are provided, the load carrier is available to all shippers.