add API to get the data type of a document property in action mod

We want to get the data type of a document property, e.g.

for (const p of document.Properties) {

    // get the data type of p here

}



const p = document.Properties.Get("my-property-name");

// or get the data type of p here

The name of the property is specified by an input parameter, so we would like to check if its data type fits our needs and return an error if it does not.

As per support that I quote, our use case is that the value of this document property could be null so it's not possible to get the value and use typeof to check the type.

Currently, there is no API for getting the type of a property. If the property has a value assigned, then you could use typeof to get the type of the returned value.

When setting a property, an exception will be thrown if the assigned value is of the wrong type.