Replace hand-rolled CLI argument parsing with Commander for command
registration and option handling. Streamline config resolution by
removing the BrickConfig type and accepting a plain source string
with BRICK_SOURCE env var support.
- Replace manual CLI dispatch with Commander-based command tree
- Simplify resolveConfig/resolveSource to a single resolveSource function
- Remove BrickConfig interface in favor of direct source string
- Move isRemote check into index-loader as a local utility
- Update loadIndex signature to accept source string directly
- Refactor CLI entry point to use modular command structure
- Add list command with placeholder implementation
- Set up type definitions for command interface
- Configure TypeScript build and package files for distribution
- Add dist output to .gitignore
yangzhaohan