Update documentation about AI Context and standardized instrumentation

What does this MR do and why?

Update the docs to document the changes recently added to the AI context.

• model_provider
• model_engine
• model_name
• flow_version
• flow_registry_version

References

Screenshots or screen recordings

Before	After

How to set up and validate locally

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Related to #580788