style: standardize YAML and Twig formatting

Jim Birchrequested to merge
issue/diagnosis-3578780:3578780-fine-tuning into 1.x
  • Normalize YAML quote style (single to double quotes)
  • Fix YAML empty object syntax ({} instead of { })
  • Format CLAUDE.md code examples with proper indentation
  • Remove trailing commas in icon.twig
  • Update package-lock.json peer dependencies

Closes #3578780

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