Aetherium - Vulkan Shader

### Fixed

- Mining a block showed no crack with Photon. The crack is now drawn after the pack's deferred passes, wherever it
  lies, and it is no longer drawn into the shadow map.
- Enchanted items and armour showed a garbled, rainbow-striped glint with packs that store packed data in their
  first output (Photon). Packs with their own glint program now draw the glint with it, over the item.

### Also fixed

- NeoForge: the game crashed at startup ("Texture does not exist") when a texture atlas ticked before it was
  first uploaded, which NeoForge does while resources are still loading.
- The shader pack screen's "Open packs folder" did nothing when the `shaderpacks` folder did not exist yet; it now
  creates the folder and opens it.