Add dependency check to CI

[okwn]

Summary

This PR adds a dedicated dependency check workflow to ensure dependencies are properly validated for vulnerabilities and licensing compliance.

Changes

• Added .github/workflows/dependency-check.yml with:
  • Dependency vulnerability scanning via actions/dependency-review-action@v4
  • Fail-on-severity set to low for comprehensive security coverage
  • Allowed licenses: MIT, Apache-2.0, BSD-2-Clause, BSD-3-Clause, ISC
  • Dependency graph validation step that generates a summary of all dependencies

Why

• Provides proactive security scanning on every push/PR
• Ensures no vulnerable dependencies are introduced
• Validates license compliance across the project

Closes #31