Add integration with GraphQL module

Problem/Motivation

To be able to expose the VG Wort field in a GraphQL schema, a dataproducer and a VG Wort field schema is required. The Drupal GraphQL module in version 4 does not automatically expose all fields, and developers have to do this manually for each instance.

To make this easier and in a unified way, the vgwort module could provide the required data producer and schema extensions.

Proposed resolution

Provide the data producer

Remaining tasks

• Implement a dataproducer, that resolves the vgwort_counter_id.value and vgwort_counter_id.url properties.
• Add a GraphQL schema for and the vgwort field and use the dataproducer to resolve these fields
• Document how to use this in your own projects

User interface changes

API changes

Data model changes