Build/Test Tools: Format copied Gutenberg style registry

[benitoalba]

Formats the generated Gutenberg style registry while it is copied into Core.

Gutenberg currently outputs registry.php with unaligned array operators and missing spaces inside non-empty dependency arrays. Running build:dev followed by a Core PHPCS scan therefore reports coding standards violations. The copy step now normalizes those known fields without requiring PHP or Composer in build-only jobs.

Trac ticket: https://core.trac.wordpress.org/ticket/65278

Testing

• npm run build:dev
• npm run grunt jshint:grunt
• php -l src/wp-includes/css/dist/registry.php
• php ./vendor/squizlabs/php_codesniffer/bin/phpcs --standard=phpcs.xml.dist src/wp-includes/css/dist/registry.php
• php ./vendor/squizlabs/php_codesniffer/bin/phpcs --standard=phpcompat.xml.dist src/wp-includes/css/dist/registry.php
• git diff --check

Before the change, PHPCS reported 34 errors and 38 warnings in the generated registry. After the change, both PHPCS rulesets pass.

Use of AI Tools

AI assistance: Yes
Tool(s): OpenAI Codex
Model(s): GPT-5
Used for: Issue research, implementation, and local validation.

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[github-actions]

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Pull request overview

Updates the Core build pipeline to normalize formatting in the copied Gutenberg style registry (registry.php) so that Core PHPCS scans pass in build-only environments without requiring PHP/Composer tooling.

Changes:

• Adds a copy:gutenberg-styles options.process hook that only targets registry.php.
• Normalizes alignment around => for the handle, path, and dependencies keys, and adjusts spacing in non-empty dependency arrays during the copy step.

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[github-actions]

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Props benitoalba.

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