fetch_samples.sh downloads four public tick samples (Dukascopy EURUSD
and XAUUSD, a broker XAUUSD feed, US500) from Hugging Face and converts
them with a small pure-Python Parquet reader. baselines.py measures
xz/zstd on raw and delta-encoded ticks for comparison.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
