Wire MBP-10 order book data through ImbalanceBarSampler into the DQN
training pipeline. No fallback — explicit data_source config: "mbp10"
(imbalance bars from 10-level order book) or "ohlcv" (1-minute candles).
Fails loudly if chosen source's data doesn't exist.
Pipeline: MBP-10 .dbn.zst → trade extraction (action=='T', native side
classification) → adaptive ImbalanceBarSampler (EWMA threshold) →
OHLCVBar → existing feature extraction.
Production: data_source="mbp10", smoketest/localdev: data_source="ohlcv".
8 files, +483/-48 lines. 3 new tests for trade extraction and pipeline.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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