This commit introduces the ability to store and display the Wikidata ID for scientific names.
Changes include:
- A database migration to add the `wikidata_id` column to the `scientific_names` table.
- An update to the `scientific_names_controller` to permit the `wikidata_id` parameter.
- An update to the scientific name form to include a field for the Wikidata ID.
- An update to the crop show page to display a link to the Wikidata page for a scientific name.