Api V2 Forced-Flow Backtest Get

Charm-into-Close track record: when the morning charm flow is stronger (or weaker) than its own recent normal, does the noon->close return lean the same way?

Scores the charm read RELATIVE to its trailing baseline rather than by raw sign -- for an index book the raw sign is structurally almost constant ("buy" nearly every day), so it degenerates to the naive baseline and tests nothing; the deviation from recent normal is the part that varies. Reads the persisted forced_flow_profile + underlying_quotes history and reports the hit rate against a naive directional baseline -- honestly, including when the sample is thin or the edge is nil. Scores TWO forecast definitions over identical sessions (full = 0DTE-inclusive close flow; smooth = first-order charm only) so the A/B is visible. Returns 200 with zeroed counts (not 404) before enough sessions have accrued, so the page can show an honest "collecting" state rather than an error.