Add n/prefer-node-protocol rule and autofix all bare builtin imports
to use the node: prefix. Simplify the simple-import-sort builtins
pattern to just ^node: since all imports now use the prefix.
Add eslint-plugin-simple-import-sort to enforce consistent import ordering:
- Node.js builtins first
- External packages second
- Relative imports last
- Named imports sorted alphabetically within each statement
