Kateryna Lovushkina opened merge request !59: Issue #3529563: Add command to fully clear Solr index at project / search_api_solr

Deletes all documents from a Solr core, including those not tracked by Drupal. This is a destructive operation that communicates directly with the Solr server and removes all indexed documents for the given Search API Solr index. Use this if you suspect Solr contains stale, orphaned, or externally added documents.