352cbc3445
_load_yaml opened config files with the platform default (locale) encoding instead of UTF-8. The shipped configs (e.g. configs/_base_/default.yaml) contain UTF-8 non-ASCII characters (em-dash, arrows, box-drawing), so load_config() raises UnicodeDecodeError on any non-UTF-8 locale (e.g. Windows cp936/cp1252), breaking scripts/train.py and scripts/eval_only.py before startup. YAML is UTF-8 by spec, and the rest of the codebase already opens text files with encoding="utf-8". Pass encoding="utf-8" here for parity.