Add MongoDB as a Vector Store

[jxblum]

trafficstars

See https://www.mongodb.com/products/platform/atlas-vector-search.

[Kirbstomper]

So I have been working on this in https://github.com/Kirbstomper/spring-ai/tree/feature/mongoDB_vectorStore

And while its almost done, (just need to filter on threshold), due to vector search in mongoDB being an atlas only feature, I can only really run the IT on my machine locally (although if the spring organization has a free tier, we could still incorporate it into the pipeline with some setup) So I will probably just settle for mocking the mongo stuff in a test. I also might add creation of the search index if it does not exist, as vector search cannot function correctly without it.

Let me know your thoughts!

[markpollack]

so we closed the PR due to the implementation not being based on the mongodb vector search offering. So now closing the issue.