Added ThreeJS documentation

[rmotafreitas]

Description ✏️

Closes No issue

Added ThreeJS documentation to preIndexedDocs.ts. This update includes:

• A new entry for ThreeJS in the preIndexedDocs object.
• Updated title, start URL, root URL, and favicon URL for better organization and navigation.

Checklist ✅

• I have added screenshots (if UI changes are present).
• I have done a self-review of my code.
• I have manually tested my code to ensure it works as expected with the new documentation entry.

[Himanshu-Singh-Chauhan]

ty for the contribution, though not sure if we need threejs by default, if you still think we need, please discuss with us on discord and we will be happy to add it. thankyou. closing this for now.😊