Create a new DrupalMago PHPCS standard

Problem/Motivation

There is a super fast PHP formatter, linter and analyzer written in Rust: mago https://github.com/carthage-software/mago . A Drupal preset for formatting Drupal code has already been committed in Mago, yay!

The problem now is that Mago fmt does not support doc comments yet for example: https://github.com/carthage-software/mago/issues/906

So we cannot replace PHPCS with Mago, and probably not for a long time. It lacks some sniffs we have in Coder and might never implement them. What we can do is establish best practices how to run Mago and Coder/PHPCS together.

Proposed resolution

• Use mago fmt and PHPCS with Coder for everything that mago does not check yet
• Define a new PHPCS Standard for that in Coder: DrupalMago
  • It includes only sniffs that mago does not cover
• Add a new helper CLI command to generate a Mago config from a PHPCS config
• Add a new helper CLI command that runs 4 parts:
  • mago fmt
  • mago lint
  • mago analyze
  • phpcs
• Add documentation about Drupal best practices what can be used from Mago

Remaining tasks

Discuss the best approaches and ideas how we can use Mago for Drupal, then implement helpers.

API changes

None.