Implementation of upsert, aupsert, get_by_ids, aget_by_ids

[eyurtsev]

• Add support for standard get_by_ids, aget_by_ids
• Add support for upsert and aupsert
• Remove add_texts and aadd_texts

[eyurtsev]

This PR requires a release of core and a release of https://github.com/langchain-ai/langchain/pull/23919