Add install command to npm package

[mrexox]

Closes #294

Summary ⚡

• Add install.js script to all os-arch dependencies

[fantua]

Is it possible that someone will use lefthook-* package directly without lefthook?
If not, than maybe we can just add one install script to lefthook package directly? Something like:

const { spawnSync } = require("child_process")
const { getExePath } = require('./get-exe');

function install() {
  if (process.env.CI) {
    return
  }

  spawnSync(getExePath(), ["install", "-f"], {
    cwd: process.env.INIT_CWD || process.cwd(),
    stdio: "inherit",
  })
}

try {
  install()
} catch(e) {
  console.warn("'lefthook install' command failed. Try running it manually.\n" + e)
}

In install phase all dependencies should be already installed.

Also Yarn 3 (berry) supports install script only for backwards compatibility. Maybe it's better to use postinstall instead (supported by both npm and yarn) 🙂

[mrexox]

Nice suggestion, @fantua! I read about issues with NPM installing dependencies before postinstall scripts, but I guess this was fixed for the last 3-5 years.

The fix: #311

Btw, feel free to open PRs :)