- Fix default base URL: https://cdn.finra.org/equity/regsho/daily (was www.finra.org/sites/default/files)
- Fix filename pattern: CNMSshvol{YYYYMMDD}.txt (was CAshvol with year/month subdir)
- Fix parser: actual file columns are Date|Symbol|ShortVolume|ShortExemptVolume|TotalVolume|Market
(was incorrectly expecting Market|Symbol|... — first col is Date, last col is Market)
- Dedupe by symbol (volume is total across all listed exchanges, not per-exchange)
- Store combined market codes (e.g. 'B,Q,N') as exchange string
- Use BEGIN/COMMIT instead of db.transaction() (node:sqlite DatabaseSync doesn't have transaction())
- Update finra_config defaults in schema.sql + migration + admin fallback