chore: update frontend tooling dependencies - #21

Changes

• Update Node engine requirement to >=22
• Update @wordpress/scripts, @wordpress/eslint-plugin, and @wordpress/babel-plugin-makepot to latest versions
• Adjust ESLint configuration to align with current plugin version
• Apply Prettier formatting to documentation files

Verified

• ✅ npm run build
• ✅ npm run lint:js
• ✅ npm run format:check

Remaining Issues

• npm audit reports 11 devDependency-related vulnerabilities
• npm audit fix --force suggests downgrading @wordpress/scripts to 19.2.4, which is not acceptable

Background

This is a maintenance branch focused on dependency updates and vulnerability remediation. We have safely updated the development toolchain and ensured that all build and quality checks pass.