Integrate Geofield module with Schema.org Blueprints

I've created a custom module that integrates the Geofield module with Schema.org Blueprints. It provides a field formatter that outputs Schema.org-compliant JSON-LD for geofield data (points and polygons).

What it does:

- Provides a formatter that converts Geofield data to Schema.org GeoCoordinates (points) and GeoShape (polygons)
- Sets appropriate default widgets (Yandex Maps if available)
- Works with Schema.org Place types and other types using geo properties

Why it's needed:

Some projects require Geofield instead of Geolocation module due to its support for polygons and other complex geometries. Currently, Schema.org Blueprints has built-in support for Geolocation but not Geofield.

Current implementation:

I've published the module here: https://github.com/sinyayadynya/schemadotorg_geofield

We can discuss:

1. Whether this should be contributed as a separate module or integrated into Schema.org Blueprints core
2. Any improvements or changes needed before contribution
3. Next steps for getting this functionality into the Schema.org Blueprints ecosystem