[MC-256668] Texture pack custom models cant read textures outside of textures/block

Moderator Note

In 1.19.3 and later, models can only access textures in the block and item texture folders by default. This is part of an optimization that makes resource loading faster!

If this broke your pack, you can fix it with one of these steps:

For custom textures, simply move them to the block or item texture folders in your namespace, and update the references to them.
To reference vanilla textures in other folders, create an atlas JSON file, following the steps in the 22w46a changelog.

Texture pack custom models cant read textures outside of textures/block

How to replicate :
1. Create a custom model
2. Use a texture in "textures/(Custom named folder)", you will get a missing texture model which did not happen in previous versions (Ie 1.19.2
more info :
If you use "textures/block" or "textures/block/(Custom named folder)" the issue won't happen