[0.9.2] - 2026-08-26

Added

• HnswIndex and BruteForceIndex (in pyvisim.image_store): an approximate
  HNSW graph and an exhaustive scan, both compiled into the package and built
  in cosine space by default.
• ExternalSearchIndex (in pyvisim.image_store): searches through an index
  built elsewhere. ExternalSearchIndex.from_faiss_index(index, vectors=None)
  adapts any FAISS index without FAISS being a dependency of this library.
• InMemoryImageEmbeddingStore.retrieve_top_k_similar ranks the gallery against
  query images and returns Candidate matches, both now owned by the store.
• InMemoryImageEmbeddingStore.save_to_disk takes the gallery vectors to
  write, for an index that hands back an approximation of what it was given.
• InMemoryImageEmbeddingStore.load_from_disk forwards keyword arguments:
  search_index=... restores a store onto a rebuilt external index, and
  anything else reaches the embedder.

Changed

• ⚠️ The store's index_type parameter is now search_index, which takes
  "hnsw", None for a brute-force scan, or an ExternalSearchIndex. Its
  quantizer parameter is now space, taking "cosine" (the default), "l2"
  or "ip".
• ⚠️ The scores of Candidate and search are distances for the built-in
  indexes, so lower is more similar. An ExternalSearchIndex reports whatever
  its own metric produces.
• The index owns the gallery vectors and the store keeps no second copy, so
  store.embeddings is read-only. Both built-in indexes decode it out of their
  own storage, which makes every access a fresh copy.
• Store files are written in a new layout; a store saved by an earlier version
  cannot be loaded by this one.

Removed

• ⚠️ pyvisim.retrieval (ImageRetriever, ImageIndex and the FAISS-backed
  IVF indexes) and pyvisim.functional. The store now covers both.
• ⚠️ The search extra, along with the faiss-cpu dependency behind it.