When lib is explicitly set in tsconfig, TypeScript does not auto-include
@types/node. Adding "types": ["node"] to both tsconfig.base.json and
packages/mcp/tsconfig.json resolves errors for process, performance, etc.
Move server code to packages/server/, add placeholder packages for
packages/ui and packages/vscode. Add tsconfig.base.json with shared
compiler options and root tsconfig.json with project references.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>