OpenImageIO: Integer wraparound in bounds check of decode_pixel leads to out-of-bounds read in TGA paletted image decoder

OpenImageIO is a toolset for reading, writing, and manipulating image files of any image file format relevant to VFX / animation. Prior to 3.0.18.0 and 3.1.13.0, the bounds check in TGAInput::decode_pixel computes k + palbytespp as unsigned 32-bit arithmetic. When k = 0xFFFFFFFC and palbytespp = 4, the addition wraps to 0, which compares less than palette_alloc_size and passes the check. The subsequent palette access uses the unwrapped k (0xFFFFFFFC) as the index, reading ~4 GB past the start of the palette buffer — SEGV. This vulnerability is fixed in 3.0.18.0 and 3.1.13.0.