Unity Living-Room Layout Tool

I’m building a small Unity application that lets homeowners visualise and rearrange their living-room furniture before they ever move a sofa. The core scene should open on an empty, resizable room where users can drag-and-drop 3D furniture models, snap them to walls or free-float them, and instantly see how different arrangements feel in real space.

Because the emphasis is on furniture arrangement, I need:

• A clean UI panel that lists the available furniture assets (chairs, sofas, tables, shelves—placeholder meshes are fine for now).
• Click-to-place, rotate, and scale controls that feel as simple as The Sims.
• Real-time collision checks so items don’t overlap or clip through walls.
• Basic save / load of a layout to JSON or ScriptableObject so users can revisit designs.

Optional niceties such as colour palettes and lighting presets can wait; the first milestone is a functional layout workflow that runs in Unity URP on desktop (Windows/macOS).

Please work in the latest LTS version you’re comfortable with, keep the code organised into clear, commented scripts, and hand over the full Unity project folder on completion.