feat: provide store opt

[antongolub]

closes #650
relates #675

const getFixedSizeArray = (size) => {
  const arr = []
  return new Proxy(arr, {
    get: (target, prop) =>
      prop === 'push' && arr.length >= size
        ? () => {}
        : target[prop],
  })
}
const store = {
  stdout: getFixedSizeArray(1),
  stderr: getFixedSizeArray(1),
  stdall: getFixedSizeArray(0),
}

const p = await $({ store })`echo foo`

p.stdout.trim() //  'foo'
p.toString()    // ''

• Tests pass