Function require_tool 

pub fn require_tool(name: &str, install_hint: &str) -> Result<(), String>

Check that an external tool is available in $PATH.

Runs <name> --version and returns Ok(()) if it exits successfully, or an error message with the install hint.

For tools that use a different version probe (e.g. koji version instead of koji --version), use require_tool_with_arg.

Example

sandogasa_cli::require_tool("fedrq", "sudo dnf install fedrq").unwrap();