This fixes an issue where Debezium would skip initial snapshot after
full-reset because the connector offset persisted in Kafka Connect's
internal connect-offsets topic.
The fix adds two strategies to delete connector offsets:
1. REST API method (Kafka Connect 3.6+): DELETE /connectors/<name>/offsets
2. Tombstone method (Kafka Connect 3.5-): Send NULL messages via kafkacat
Reference: https://debezium.io/documentation/faq/#how_to_remove_committed_offsets_for_a_connector
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>