Spring-ai Implement Anthropic Claude3 Message API client support (direct)

  This commit introduces support for the Anthropic Claude3 Message API
  (https://api.anthropic.com), enabling direct interaction with its services.
  This is not a Bedrock Anthropic Claude3 implementation!

  Changes include:

  - Implementation of a low-level client, AnthropicApi, to interact with
    the message API endpoints specified in the Anthropic documentation
    (https://docs.anthropic.com/claude/reference/messages_post), including support for streaming.
  - Addition of AnthropicApi tests to ensure functionality and reliability.
  - Support for multimodal requests within AnthropicApi.
  - Adding the spring-ai-anthropic and boot starter into BOM and parent POM modules for streamlined usage.
  - Add Anthropic Auto-configuration and Boot Starter for seamless integration into existing projects.
  - Implementation of AnthropicChatClient with capabilities for synchronous and streaming communication,
    including support for multimodal messages.
  - Inclusion of both unit and integration tests to validate functionality across various scenarios.
  - Add Antora documentation with comprehensive guidance on using AnthropicApi and AnthropicChatClient.
  - Add of Ahead-of-Time (AOT) hints for AnthropicApi.

Comment From: markpollack

wow merged in ce2bb131e567d551863166329b00824fcb746d3a