Add course versioning and content history

[RUKAYAT-CODER]

Background

Course content changes should be tracked with version history for audit trail and rollback.

• Content changes not tracked
• Cannot see version history
• No rollback capability
• Audit trail missing

Acceptance Criteria

• Version table created
• Content changes tracked
• Version history API
• Rollback to previous version
• Diff view for changes
• E2E tests for versioning

[joelmadaki77-cyber]

@joelmadaki77-cyber has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hello maintenance I’ll like to work on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @joelmadaki77-cyber to this issue.

[drips-wave]

Congratulations, @joelmadaki77-cyber! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @joelmadaki77-cyber: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊