bug: QR code redirect fix

[natalierobbins]

📄 Description

• Before, seeds were generating a full redirect URL, with domain predetermined by env vars. Now, the QR code just encodes the survey code itself, and our client is responsible for building its own redirect URL and injecting the survey code inside of it
  • This makes it so any deployment URL can use any QR code
• Code validation still resides inside of our /survey path, so an invalid code (either a random QR code, or a QR code containing an invalid code) will try to redirect to /survey, then immediately bounce back to the apply referral page.

Valid seed scan

• Can create a new survey or re-enter an in-progress survey using the scanned QR code:

Screen.Recording.2025-11-14.at.3.59.20.PM.mov

• Will still bounce when trying to re-enter a completed survey:

Screen.Recording.2025-11-14.at.4.14.47.PM.mov

Invalid seed scan

• Random QR code will bounce:

Screen.Recording.2025-11-14.at.4.06.09.PM.mov

✅ Checklist

• Tests added/updated where needed
• Docs added/updated if applicable
• I have linked the issue this PR closes (if any)

🔗 Related Issues

💡 Type of change

Type	Checked?
🐞 Bug fix	[x]
✨ New feature	[ ]
📝 Documentation	[ ]
♻️ Refactor	[ ]
🛠️ Build/CI	[ ]
Other (explain)	[ ]

🧪 How to test

📝 Notes to reviewers