Should convex decomposition return an option or a result?

I ran into
```
A compound shape must contain at least one shape.
```

I'm generating lots of convex decomposition colliders like this:

```rust
let contours = self.contours_with_holes_flat(bitmap_to_pixels, simplify_epsilon);
if contours.len() < 4 {
return vec![];
}
let indices = (0..contours.len() as u32 - 1)
.map(|i| [i, i + 1])
.collect::>();
let collider = ColliderBuilder::convex_decomposition_with_params(
&contours,
&indices,
&VHACDParameters {
resolution: 64,
fill_mode,
..Default::default()
},
)
.build();
```

The assertion in `parry2d-0.17.0\src\shape\compound.rs:35:9` causes a panic, and can't do much about it. I don't really know when exactly the function fails to generate a shape, and my attempt to not let too small contours only helps for some other panics...

I would prefer no panics, and let the user handle the issues (Option or Result).