Memory exposure via uninitialized Read buffer

Memory exposure in gfx-auxil 0.10.0 and earlier allows attackers to read uninitialized heap contents through read_spirv. The function reserves a Vec without initializing its storage, then passes that buffer to a caller-supplied Read implementation before setting its length. Exploitation requires code that can supply the Read implementation; consequences include disclosure of stale heap data and undefined behavior in the consuming process.