Adding Native OpenSearch support for Mem0

[seetharam-rajagopal]

Description

Mem0 currently lacks native support for OpenSearch as a vector store. Given OpenSearch's popularity as a scalable open-source search and analytics suite with k-NN vector search capabilities, adding direct support would benefit many users.

Fixes #2200

Type of change

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Added appropriate unit tests.

• Unit Test

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• [] New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

Maintainer Checklist

• closes Feature Request: Direct Support for OpenSearch as a Vector Store #2200
• Made sure Checks passed

[CLAassistant]

All committers have signed the CLA.

[Dev-Khant]

@seetharam-rajagopal Can you please add pip install opensearch-py to MAKEFILE because tests are failing because of it?

[seetharam-rajagopal]

@Dev-Khant Updated the Makefile

[Dev-Khant]

@seetharam-rajagopal Can you please add this to the docs? You can take reference from this PR and also update docs.json?

[seetharam-rajagopal]

@Dev-Khant I have updated the documentation

[Dev-Khant]

@seetharam-rajagopal Changes look good to me. Thanks for the contribution!!