On Windows, Python defaults to the active code page (cp1252) for
subprocess I/O. HuggingFace CLI outputs U+2713 (✓) when validating
tokens, which cp1252 cannot encode, crashing the download process.
Set PYTHONUTF8=1 and PYTHONIOENCODING=utf-8 in the subprocess
environment so Unicode output from hf/pip/llama-server is handled
correctly.
Fixes#1543
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>