Capgo Native Builds

This handles Capgo's cloud build service for compiling native iOS and Android binaries when you don't want to build locally or set up your own CI. It covers the full workflow: CLI login with API keys, storing signing credentials (Apple certificates, provisioning profiles, Android keystores), requesting builds, and getting either direct download links or automatic uploads to TestFlight and Play Store. The interactive `build init` command is useful for first-time iOS setup since it can generate and save signing material with minimal manual steps. Credentials live in your local `~/.capgo-credentials` directory and only get sent to Capgo during the actual build job. Good for teams that want hosted builds without managing Jenkins or GitHub Actions runners, though you'll still need your own Apple and Google developer accounts.