Creates a draft post.
For 3rd-party apps, memberId is a required field.
In categoryIds, only categories that already exist will be added to the draft post. Including
categoryIds that do not exist will not return an error, but they will not be added to the categoryIds array.
If some of the categories exist, those will be added while those that do not exist will not be added to categoryIds.
You can check which categories are available with
List Categories (SDK | REST).
You can only call this method when authenticated as a Wix app or Wix user identity.
This method doesn’t return any custom errors, but may return standard errors. Learn more about standard Wix errors.