Add Hugging Face Hub integration for safetensor files

- Add `tsr hf search` to search HF models with safetensor files
- Add `tsr hf get` to view model info and list safetensor files
- Add `tsr hf files` to list safetensor files in a model
- Add `tsr hf dl` to download safetensor files from HF

Uses official huggingface_hub library for API access.
Only safetensor files are supported (enforced at search and download).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pyproject.toml

@@ -10,6 +10,7 @@ dependencies = [
     "rich>=13.0.0",
     "typer>=0.15.0",
     "websocket-client>=1.9.0",
+    "huggingface_hub>=0.25.0",
 ]
 
 [project.optional-dependencies]
@@ -98,6 +99,10 @@ ignore_missing_imports = true
 module = ["scalar_fastapi.*"]
 ignore_missing_imports = true
 
+[[tool.mypy.overrides]]
+module = ["huggingface_hub.*"]
+ignore_missing_imports = true
+
 [tool.pytest.ini_options]
 testpaths = ["tests"]
 addopts = "-v --cov=tensors --cov-report=term-missing"