nx_gguf_load_test.nx

nx_gguf_load_test.nx -- smoke for nx_gguf_load.nx. Builds a synthetic GGUF blob in memory with two tensors: tensor[0] "score" : F32 shape [2,2] = {1.0, 2.0, 0.5, -1.0} tensor[1] "weight" : Q8_0 shape [32] scale=0.5, qs={0,1,2,...,31} => values {0, 0.5, 1.0, ..., 15.5} Verifies: - parse + name lookup + not-found verdict - format-helper bytes/values per block + total bytes - f32 → Q10 unit conversions on canonical bit patterns - f16 → Q10 unit conversions on canonical bit patterns - end-to-end load + dequant for F32 and Q8_0