Exclude package.json and package-lock.json from Prettier formatting

[Copilot]

Package manager files should not be reformatted by Prettier to avoid interfering with package manager tooling and maintain their canonical format.

Changes

• Created .prettierignore with patterns for package.json, package-lock.json, and other generated files
• Updated npm scripts in actions/setup/js/package.json:
  • Added !../../../**/package.json and !../../../**/package-lock.json exclusions to format:pkg-json and check:pkg-json
  • Removed --ignore-path /dev/null to respect .prettierignore

Before/After

# Before: Formatted all JSON including package files
npx prettier --write '../../../**/*.json' --ignore-path /dev/null

# After: Excludes package manager files
npx prettier --write '../../../**/*.json' '!../../../**/package.json' '!../../../**/package-lock.json'

The dual approach (.prettierignore + explicit exclusions) ensures package files are protected both in general usage and in targeted npm scripts.

Original prompt

Update prettier formatting options to ignore/skip package.json and package-lock.json

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