Calls the Hugging Face Hub API to list all .gguf files in a repository,
along with their sizes. Useful for choosing a quantization level before
calling llamacpp_download_model().
list_hf_gguf_files(.repo, .timeout = 30)A tibble with columns filename, size_gb, and url.
Hugging Face repository ID in "owner/model" format
(e.g. "Qwen/Qwen3-8B-GGUF").
Request timeout in seconds (default: 30).