create-cli

Design and build command-line tools, both the interface spec (args, flags, subcommands, help, output modes, errors, exit codes, config) per clig.dev and the implementation using Magnus's agent-ready Rust house style (clap derive, global --json, keychain/op/file secret backends, in-repo agent skills, AGENTS.md) modeled on sparebank1-cli and skatteetaten-cli. Use when the user wants to create a new CLI, design a CLI interface, scaffold a command-line tool, or make an existing CLI agent-friendly.