Weaviate 1.15.1 patch release

Weaviate v1.15.1 is a significant patch release addressing over 15 bugs in indexing, sorting, aggregation, stability, and UX. The release includes fixes for vector and object/inverted stores, improved sorting implementation with new tests, seven aggregation issues fixed, a rare critical bug related to data race, and several UX improvements. This release ensures increased stability, proper updates reflection, and better user experience.