Fix Cabinet Snapping & Alignment Issues in Three.js/WebGL 3D Kitchen Planner

We have an existing web-based 2D/3D kitchen design application built using Three.js, React Three Fiber, and WebGL.
We need an experienced Three.js developer to investigate and fix issues related to cabinet snapping, positioning, and alignment within the room editor.

Existing Application:
https://app.diydesignspace.com/thertastore

Issues to Investigate and Fix
Cabinets not snapping accurately to adjacent cabinets or walls.
Unexpected gaps or overlaps when positioning cabinets.
Incorrect snapping behavior after rotating cabinets.
Inconsistent snapping when dragging or repositioning objects.
Potential coordinate, bounding-box, or collision-detection issues.
The exact root causes and reproduction conditions will need to be confirmed during debugging.

Required Skills
Strong experience with Three.js and React Three Fiber.
Solid understanding of 3D coordinates, transformations, and bounding boxes.
Experience implementing object snapping and collision detection.
JavaScript/React debugging and optimization.
Experience with 2D/3D room planners or product configurators is preferred.

Expected Deliverables
Identify and explain the root cause of the snapping issues.
Implement reliable snapping and alignment fixes.
Ensure existing placement and rotation features continue working correctly.
Test the fixes across different cabinet sizes, positions, and room layouts.
Provide the updated source code and a brief summary of changes.

Additional Information
This is an existing application, not a new development project. We are looking for someone who can understand the current codebase, isolate the issue, and implement a clean, maintainable fix.

Please share examples of relevant Three.js projects, especially those involving drag-and-drop object placement, snapping, or 3D configurators.