FFI fails handling some return types

[ekgame]

I was trying to implement textures for Rayua, but I'm having trouble with the first step.

Reproduction steps:

• Checkout feature/more-functions branch from https://github.com/ekgame/rayua/tree/feature/more-functions
• Run uiua run examples/textures.ua
• The console should print:

  INFO: FILEIO: [./examples/cats.png] File loaded successfully
  INFO: IMAGE: Data loaded successfully (720x720 | R8G8B8 | 1 mipmaps)
  Segmentation fault (core dumped)

  The issue seems to be related to the return type:

  # lib.ua
  Texture ↚ "{unsigned int; int; int; int; int}"
  LoadTexture ← Rl {Texture "LoadTexture" "const char*"} {∘}

  Changing the Texture type signature to "{unsigned int; int; int; int}" (missing last int) fails to open file and returns an array with nonsense data, but does not segmentation fault.