UI rearangement

[Kupinaaa]

To save development time and reduce complexity, I chose to add a selector component from shad/cn instead of writing my own. It should not bloat our application too much and, in my opinion, is a great solution given our time constraints.

This PR:

• Adds shad/cn selector
• Adds the new floor selector
• Removes unnecessary library and floor selection checks in the time selection component