Add support for Amazon Bedrock models

[Cerrix]

Overview

This PR adds support for Amazon Bedrock, allowing TextGrad users to leverage a variety of foundation models from AI21 Labs, Anthropic, Cohere, Meta, Mistral AI, Stability AI, and Amazon through a single API.

Key Changes

• Implemented support for Amazon Bedrock in the get_engine function
• Added compatibility for Meta, Anthropic, Cohere, Mistral, and Amazon models
• Introduced a new naming convention for Bedrock models: bedrock-<model_name_id> (here the model id list)

Usage

To use a Bedrock model, call the get_engine function with the Bedrock model name ID prefixed by "bedrock-". For example:

engine = get_engine("bedrock-anthropic.claude-3-sonnet-20240229-v1:0", max_tokens=2048)

Authentication

The PR supports two authentication methods:

1. AWS environment using AWS Roles
2. Environment variables:

• AWS_DEFAULT_REGION (optional)
• AWS_SECRET_ACCESS_KEY
• AWS_ACCESS_KEY_ID
• AWS_SESSION_TOKEN (optional)

Supported Models

This PR adds support for the following model families:

• Meta
• Anthropic
• Cohere
• Mistral
• Amazon

A complete list of supported model IDs will be added to the documentation.

Testing

• Tested with various Bedrock models
• Verified authentication methods
• Ensured compatibility with existing TextGrad functionality

Feedback

I welcome any feedback or suggestions for improvement. Please let me know if any additional changes or clarifications are needed.