Fix: allow preview of page with unpublished parent

[laylahoogeveen]

Ticket:

Description of changes

Unable to preview a sub-page if parent page is not published.

Presentation mode returns a 404 page when manually adding the URL to the address bar.

How to validate the changes

• Create a page under an unpublished parent page.
• Check "link to page". The first part of the slug shouldn't be undefined anymore.
• Navigate to the page in presentation mode. This shouldn't render a 404 anymore

✅ Definition of Done

This checklist helps with risk management during software development. It is not a mandatory list to fully check off, but a basis for thinking about quality, safety, and best practices. Feel free to adapt it for your own project — as long as the risks are consciously managed.

📄 Documentation & Knowledge Sharing

• Changes are documented in the code and/or README.md
• Relevant Notion pages are updated

🧪 Testing & Quality

• Changes are covered by unit/integration/end-to-end tests
• GitHub Actions (CI/CD) pass successfully
• Reviewer has tested and verified the changes locally

📊 Monitoring & Performance

• Relevant metrics (e.g. in Datadog) are added or updated
• Performance and scalability have been considered and tested if needed

🔐 Security & Privacy

• The changes comply with our Secure software development policy
• No personal data or privacy-sensitive information is affected
• Input validation, authentication, and authorization are properly handled

🧩 Traceability & Readiness

• A Jira ticket is linked, and the ticket number is in the PR title (e.g. [R2025-1234] Meaningful title)
• No unresolved TODOs remain in the code (unless followed up with a Jira ticket)

🤝 Review & Collaboration

• Code is reviewed by at least one team member
• Merge responsibility and timing are agreed upon
• Team members are informed (e.g. via Slack or daily stand-up)

[stijn-q42]

nice, easy fix :D