Create low-fidelity onboarding wireframes

## Summary

Sketch the first concepts for how users may experience StayWithMe.

## Why?

Wireframes help explore ideas before investing time in implementation.

## Tasks

- Design onboarding screens.
- Map the user journey.
- Review layouts for simplicity.
- Gather early feedback.

## Success Criteria

- Initial wireframes are complete.
- User flow is documented.