chore: adjust public app url to staging

[qhantom]

DESCRIPTION

This PR adjusts the app url to be mapped to the staging environment.

TO-DO

• [x] implement and update tests
• [x] update docs
• [x] pull main & resolve merge conflicts
• [x] check Vercel deployment

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Updated (UTC)
app	✅ Ready (Inspect)	Visit Preview	Mar 21, 2024 5:28pm
docs	✅ Ready (Inspect)	Visit Preview	Mar 21, 2024 5:28pm

[nx-cloud[bot]]

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