* feat(milvus): add delete_vectors to MilvusStore
Adds delete_vectors(ids) so the ErasureCoordinator can erase embeddings
on a Milvus backend. Ids are escaped with _format_milvus_value before
building the delete expression, and the backend delete count is returned
so a delete that removed nothing is distinguishable from a failure.
* test(milvus): cover delete_vectors incl. erasure integration
Unit tests assert the single-id equality expression, multi-id in
expression, id escaping, empty-id noop, missing-collection and backend
error paths. Integration tests bind MilvusStore as a VectorStore backend
and assert ErasureCoordinator reports the vector leg erased.
* test(milvus): cover vector store delete facade
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Co-authored-by: Mohd Kaif <98801504+KaifAhmad1@users.noreply.github.com>
Co-authored-by: Sameer Kadam <sskadam6305@gmail.com>
Co-authored-by: Sameer Kadam <sameerkadam@Mac.lan>
