Fix Drupal coding standards violations in custom module and theme

[Copilot]

Custom PHP files and theme CSS lacked @file doc comments, proper use statements, and minor formatting issues. No phpcs.xml.dist existed, leaving CSS full of false positives from modern CSS syntax (custom properties, multi-line values, :where()).

PHP (markie.module, markie.install, markconroy.theme)

• Added @file doc comments with descriptions
• Replaced fully-qualified \Symfony\...\AccessDeniedHttpException with a use import
• Removed leading \ from use \Drupal\node\Entity\Node
• Fixed doc comment asterisk alignment; added trailing period to inline comment
• Removed dead commented-out code; split an 85-char line to stay within 80-char limit

CSS (breadcrumbs.css, pager.css, base.css, homepage.css, README.md)

• Added missing trailing newlines
• Removed blank line before closing } in .homepage__nav ul

phpcs.xml.dist (new)

Adds a project-level PHPCS config so vendor/bin/phpcs works without flags:

• Applies Drupal + DrupalPractice standards to web/modules/custom/ and web/themes/custom/
• Excludes CSS sniffs that produce false positives on modern CSS (Squiz.CSS.MissingColon, Squiz.CSS.SemicolonSpacing, Squiz.CSS.Indentation, Drupal.CSS.ClassDefinitionNameSpacing.MultipleSelectors)
• Suppresses the version key warning for non-distributed custom theme/module info files