COIN-M daily trades files are truncated and is_buyer_maker is always true

Two problems with the COIN-M trades archive under data/futures/cm/daily/trades/, both still present.

- Files are cut short. Recent files contain only the first two hours or so of the day instead of the full 24.
- is_buyer_maker is always true. Since 2026-07-01, every row in every COIN-M trades file has is_buyer_maker=true with no false values at all.

Both look like export-side issues rather than bad data: /dapi/v1/trades returns a normal mix, and your own aggTrades archive is healthy and disagrees with the trades file for the same trade IDs.

Could the affected files from 2026-07-01 onward also be regenerated? Fixing only new files leaves about two months unusable, and there's no other way to get that period- /dapi/v1/aggTrades and /dapi/v1/historicalTrades both reject anything older than two days with -4166.

Start with the affected archive under data/futures/cm/daily/trades/ and compare its rows with /dapi/v1/trades and the existing aggTrades archive for the same trade IDs. Done means COIN-M files from 2026-07-01 onward contain the full day and preserve both is_buyer_maker values, with the affected period regenerated.

Written by the indexing model from the issue text.