Add linting command

[mikeybinns]

A command to run the linting tools and provide a clean simple output for the result e.g.:

ESLint: 96 Errors, 14 Warnings
Typescript: 12 Errors, 26 warnings, 2 fixable
PHP: 129 Errors, 12 Warnings, 40 fixable
Stylelint: Not configured

We should also add a parameter to the smash config for linting baseline, and then this command can throw an error if the linting is finding more errors than the existing baseline for commit checks. No baseline config would default to zero errors as the baseline.

import type { SmashConfig } from "@atomicsmash/cli";
export default {
  projectName: "launchpad",
  themePath: "public/wp-content/themes/launchpad",
  lintingBaseline: {
    eslint: {
      errors: 96,
      warnings: 14,
      fixable: 0,
    }
  }
} satisfies SmashConfig;

[mikeybinns]

Started a proof of concept for ESLint in the feature/add-linting-command branch.