bijection init

Create a new Bijection project in [dir], the current directory by default: a `bijection/` directory with a sample schema, query and mutation, `bijection.json`, `.gitignore` and a README.
The backend template needs nothing else installed. Customer apps use React and Vite; the react-vite template writes the app and installs its dependencies with your package manager (pnpm, bun, yarn or npm).
It then generates `bijection/_generated/`, so the project typechecks before it has a deployment.

Then run `bijection login` and `bijection dev`.

Usage:
  bijection init [dir] [flags]

Flags:
  -h, --help              help for init
      --template string   Project template (backend, react-vite) (default "backend")