Mongo db vector store

[Pash10g]

Summary

This PR implements MongoDB Atlas Vector Store node enabling vector similarity search capabilities in n8n's LangChain integration.

Implementation Details

• MongoDB Atlas Vector Store integration with LangChain
• Operations: load, insert, retrieve, update
• Namespace management and collection handling
• Vector index validation
• Enhanced error handling

Testing Steps

1. Prerequisites:

   • MongoDB Atlas cluster
   • Vector search index configured
   • Valid connection string

2. Test Operations:

   // Example workflow
   1. Insert Operation
   - Input: documents with embeddings
   - Expected: vectors stored in MongoDB
   
   2. Retrieve Operation
   - Input: query vector
   - Expected: similar documents returned
   
   3. Update Operation
   - Input: modified vectors
   - Expected: database updated

Related Linear tickets, Github issues, and Community forum posts

Include links to Linear ticket :

Docs : n8n-io/n8n-docs#2798

Review / Merge checklist

• PR title and summary are descriptive. (conventions)
• Docs updated or follow-up ticket created.
• Tests included.
• PR Labeled with release/backport (if the PR is an urgent fix that needs to be backported)

[CLAassistant]

All committers have signed the CLA.

[Joffcom]

Hey @Pash10g,

Thanks for the PR, We have created "GHC-657" as the internal reference to get this reviewed.

One of us will be in touch if there are any changes needed, in most cases this is normally within a couple of weeks but it depends on the current workload of the team.