`buffer.byte_swap_u32` reverses the byte order of a `U32`. Applying it twice
returns the original value.
Reference CPU implementation:
```rust
let swapped = value.swap_bytes();
```
WGSL spelling note: the lowering uses byte masks and shifts:
`0x000000ff << 24`, `0x0000ff00 << 8`, `0x00ff0000 >> 8`,
and `0xff000000 >> 24`.