Quantization Error unsupported safetensor dtype F8_E4M3

Using tensor-tools to quantize a flux finetine at little-lake-studios/demoncore-flux on hf hub
https://huggingface.co/little-lake-studios/demoncore-flux/

```
tensor-tools quantize demonCORESFWNSFW_fluxV13.safetensors --out-file Q8_0.gguf --quantization q8_0
```
gets an error
```
Error: unsupported safetensor dtype F8_E4M3
```

Start by reproducing the `tensor-tools quantize` command against the linked Flux model and trace where the safetensor dtype is handled. Identify the quantization path for `F8_E4M3`; done means the reported model can be quantized with `q8_0` without the unsupported-dtype error.

Written by the indexing model from the issue text.