feat(docs): add PGVectorStore (#30950)
Thank you for contributing to LangChain!
- **Adding documentation for PGVectorStore**:
docs: Adding documentation for the new PGVectorStore as a part of
langchain-postgres
- **Add docs**: The notebook for PGVectorStore is now added to the
directory `docs/docs/integrations`.
As a part of this change, we've also updated the VectorStore features
table and VectorStoreTabs
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Co-authored-by: Chester Curme <chester.curme@gmail.com>
Co-authored-by: Eugene Yurtsev <eyurtsev@gmail.com>
