Replace SSE streaming with non-streaming JSON for Anthropic API.
Add llm_chat_tools() returning structured llm_response_t with text
and tool_use blocks. Implement tool registry with dispatch-by-name
and web_search tool via Brave Search API (direct + proxy support).
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Anthropic Messages API integration with streaming response.
Parses content_block_delta SSE events, accumulates text tokens.
API key and model stored in NVS.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>