Currency rates and conversion CLI.
```sh
cargo install --path crates/dee-rates
```
```sh
dee-rates get USD
dee-rates get USD EUR --json
dee-rates convert 100 USD EUR
dee-rates convert 100 USD EUR --json
dee-rates list --json
```
- --
Use `--json` for automated workflows.
```sh
dee-rates --help
dee-rates <command> --help
```