Amazon Bedrock API Keys

[gulench]

Support Amazon Bedrock API Keys also as a means of authentication/authorization.

Expected Behavior

Spring AI also accepts "Amazon Bedrock" API Keys as an alternative means of authentication/authorization to the AWS SDK Credentials (in the form of AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY)

Current Behavior

Spring AI currently supports authentication/authorization using the AWS SDK credentials (AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY)

Context

This feature is about a better and uniform developer experience. To quote the blog post Accelerate AI development with Amazon Bedrock API keys:

Today, we’re excited to announce a significant improvement to the developer experience of Amazon Bedrock: API keys. API keys provide a new way to access the Amazon Bedrock APIs, streamlining the authentication process so that developers can focus on building rather than configuration.

Please suggest if there is a way to customize the existing extension points to utilize the Amazon Bedrock API Keys (AWS_BEARER_TOKEN_BEDROCK) instead of the AWS SDK Credentials.