CI Pipeline: Sample Data Validation Workflow Modernized to Node.js 20

What Changed

The Sample Data Validation GitHub Actions workflow was updated to resolve persistent build failures caused by outdated npm 6.14.18 (“cb() never called!” errors). The workflow now uses actions/setup-node@v4 with Node.js 20 LTS, npm caching enabled, and npm ci for deterministic dependency installation.

Additional changes include package-lock.json synchronization to add missing [email protected], gitignore patterns for TypeScript build artifacts, and workbook preview image validation logic expanded to accept “Light/Dark” theme naming conventions alongside “Black/White”.

Affected Files

.github/workflows/sample-data-validation.yaml
.gitignore
.script/utils/workbookCheckers/previewImageChecker.js
.script/utils/workbookCheckers/previewImageChecker.js.map
package-lock.json