Extracts all argument-parsing and help logic into cli.rs:
- -h / --help: colored usage and options summary
- -V / --version: print version from Cargo.toml
- Unknown flags produce a styled error with a hint
- At least one file required; missing-file error is styled
- Multiple files accepted; exit code 1 if any file has parse errors
Jooris Hadeler
415dea6fd2