[Feat] Rag Docs

[harshalmore31]

This pull request reorganizes and expands the documentation for RAG (Retrieval-Augmented Generation) vector database integrations in Swarms. It introduces a new section with comprehensive guides for multiple vector databases, adds a detailed integration guide for ChromaDB, and updates the navigation structure to reflect these changes.

Documentation Structure Improvements:

• The docs/mkdocs.yml navigation is restructured to group all RAG-related content under a new "RAG Vector Databases" section, listing individual guides for each supported database.
• A new overview page, rag-vector-databases/overview.md, summarizes available integrations, key features, and guidance for choosing the right vector database for different use cases.

New Integration Guide:

• A comprehensive guide for integrating ChromaDB with Swarms agents is added (rag-vector-databases/chromadb.md). This includes setup instructions, a full code example with unified LiteLLM embeddings, use cases, performance tips, deployment options, configuration, best practices, and troubleshooting.

These changes make it easier for developers to find, understand, and implement RAG solutions with a variety of vector databases using Swarms.

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References:
[1] [2] [3]

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📚 Documentation preview 📚: https://swarms--1067.org.readthedocs.build/en/1067/