Improve Spring AI Bedrock Converse API Integration

[tzolov]

Extend the Spring AI Bedrock Converse integration with support for the following Bedrock Converse and ConverseStream API features:

• additionalModelRequestFields - Additional inference parameters that the model supports, beyond the base set of inference parameters that Converse and ConverseStream support in the inferenceConfig field.
• ConverseMetrics and ConverseStreamMetrics - Metrics for a call to Converse and ConverseStream
• Guardrail, Include a guardrail with Converse API - Guard conversational apps that you create with the Converse
• Provider better control over the built-in API retry configuration capabilities.