4549: Hugging Face embedder improvements r=dureuill a=dureuill
Architectural changes/Internal improvements
### 1. Prefer safetensors weights over pytorch weights when available
safetensors weights are memory mapped, which reduces memory usage of supported models.
### 2. Update candle
Updates candle to `0.4.1`, now targeting crates.io and the tokenizers to `v0.15.2` (still on github).
This might fix https://github.com/meilisearch/meilisearch/issues/4399 thanks to the now included https://github.com/huggingface/candle/issues/1454
Co-authored-by: Louis Dureuil <louis@meilisearch.com>
