Establish quarterly content review cadence

[scubaninja]

Need

GitHub UI screenshots and feature references can go stale. A scheduled review cadence ensures content stays current.

Suggestion

• Set a quarterly calendar reminder to review:
  • Screenshots in content/shared-images/
  • GitHub UI references in exercise steps
  • Model names referenced in Copilot exercises (e.g. 5-bonus.md)
  • Azure/deployment instructions
• Consider adding a 'Last reviewed' date to each workshop README