Add missing id, sessionID, and messageID to MCP tool attachments

Improvements

• CoreRemove unnecessary deep clones from session loop and LLM stream
• CoreRemove User-Agent header assertion from LLM test to fix failing test
• TerminalUse structuredClone instead of remeda's clone for better performance and native support@mhart
• DesktopRestore settings header mask
• DesktopDon't spawn sidecar if default is localhost server
• SDKBuild SDK to dist/ instead of dist/src