Patch Changes

• 77775a4: feat(mcp): expose statusCode, url, and responseBody on MCPClientError for HTTP transport failures

  MCPClientError now carries structured HTTP context when it originates from the streamable HTTP transport. This lets downstream consumers (e.g. agent frameworks that need to decide whether to fall back from streamable HTTP to legacy SSE transport per the MCP spec) branch on the actual response status without parsing the error message string.

  Fields are optional — they remain undefined for stdio transport errors and for non-response failures (network errors, aborts).