Add Pre-commit Hooks and Quality Gates

[patdhlk]

Description

Add pre-commit hooks to demonstrate quality gates for requirements, while noting that ubCode provides real-time validation.

Acceptance Criteria

• Create .pre-commit-config.yaml with:
  • RST linting (doc8 or rstcheck)
  • Sphinx build check
  • Link validation
• Document in docs/how-to-guides/quality-gates.rst
• Show CI integration in GitHub Actions
• Ontology
• Add Enterprise Tip: ubCode catches these issues in real-time before commit