Export .Off not include color in face.

[ricaun]

Describe the bug
I was experimenting with .off files and noticed when exporting the to .off file the color is not included in the faces.

To Reproduce
Open the sample MultipleMeshes.bim and export to .off.
After importing the exported file to the viewer the color of the faces is not included.
The file exported does not include the color.

Expected behavior
Expected the color to be included in the face of the .off file.

This is the line that should fixed.
https://github.com/kovacsv/Online3DViewer/blob/0d9998a656b84e2a9aebdef18a03759d0bc8df27/source/engine/export/exporteroff.js#L30C1-L32C5

Here is the reference of the off file:
Reference: OFF files