M15 trail arm 0.70 (validated grid) + backtest/live parity hardening

Parity: replay now applies the live _apply_regime_filter_live method
under the live guard (function-identity, default-off); unregistered-pair
fallback applies the config.json overlay; parity sweep gains direct
ATR/vol-regime assertions; regime-filter semantics test added.

Trail campaign: --trail-arm/--trail-dist research flags; 30-cell grid on
5yr M15 refuted the earlier-arm hypothesis and found the 0.70-0.80 arm
plateau. Shipped M15-only trail_arm_r=0.70 (factory override):
+210.7R PF 1.35 WR 57.8% vs +175.7R PF 1.30 WR 53.9% baseline; both
halves and 2024-06->2025-03 OOS better (+57.4 vs +45.4); 5yr max-DD
clause (33.9R vs 29.1R) explicitly waived by owner. M5 unchanged.
Factory replay reproduces the grid cell trade-for-trade; 201/201 tests.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VPNF37MP9Kuv62B1VBrZ1b

CLAUDE.md

@@ -24,7 +24,7 @@ This file is the authoritative developer/agent reference. The human-facing docs
 | `pair_signals/__init__.py` | 52 | `PAIR_PRODUCERS` registry + `produce_signal()` |
 | `pair_signals/xauusd.py` | 71 | XAU config factory + per-timeframe overrides (docstring = validation record) |
 | `main.py` | ~348 | CLI: `python main.py --pair XAUUSD --timeframe H1 --detail/--json` |
-| `test_all.py` | ~2800 | QA suite: **199 tests in 13 modules**, no live API needed. Must stay green. |
+| `test_all.py` | ~2800 | QA suite: **200 tests in 13 modules**, no live API needed. Must stay green. |
 | `backtest/gpu_backtest.py` | ~2231 | Bar-replay backtester (CuPy→NumPy fallback) using the real `SignalAggregator` |
 | `backtest/diagnose_filters.py` | 609 | Filter-diagnosis tooling |
 | `backtest/research/` | — | Calendar research infra (`ff_calendar_scraper.py`, `calendar_store.py`) + result CSVs |
@@ -80,7 +80,7 @@ EMA 9/21/50/200 (`ema_mode`: `"4ema"` default or `"2ema"` = 50/200 only); RSI 14
 | `min_tp_cost_multiple` | 30.0 | spread gate: TP1 distance must be ≥ cost × this (= $9 on XAU). Validated: sub-$10 targets lose |
 | `min_sl_pips` | 80.0 | SL floor in pips ($8 on XAU) |
 | `tp_floor_rr` | 0.5 | TP1 floor as fraction of SL distance (M15 factory overrides to 1.0) |
-| `trail_arm_r` / `trail_dist_r` | 0.6 / 0.75 | trailing exit: once favorable excursion ≥ arm×risk, stop trails dist×risk behind best price (bar-close updates). TP1 becomes advisory. Validated on 12mo M5: +105R vs +48R static. 0 disables |
+| `trail_arm_r` / `trail_dist_r` | 0.6 / 0.75 | trailing exit: once favorable excursion ≥ arm×risk, stop trails dist×risk behind best price (bar-close updates). TP1 becomes advisory. Validated on 12mo M5: +105R vs +48R static. 0 disables. **M15 factory overrides arm to 0.70** (2026-07-21 grid: +210.7R vs +175.7R/5yr, OOS +57.4 vs +45.4; DD clause waived by owner — see factory docstring) |
 | `pb_trail_arm_r` / `pb_trail_dist_r` | 0.8 / 0.75 | trailing params for XAU_PB pullback trades (tighter stops → arm later) |
 
 ### NewsConfig
@@ -256,6 +256,7 @@ Default confirmation map (same in the factory, the bot, and backtest usage): M5
 - M5: append hour 9 UTC to blocked hours (6-yr replay: +207.1R vs +178.3R; M15-and-up keep hour 9 — it's positive there). Enable BUY-only chart patterns (`cp_enabled=True`, `cp_patterns=["inv_hs","double_bottom","bull_flag"]`): 12mo +41.8R PF 1.60 (train/val both positive), 5yr +65.2R PF 1.48; bearish CP dropped (OOS −3.21R). M15/H1 CP remain disabled (all failed OOS).
 - M15: `signals.tp_floor_rr = 1.0` (1R minimum targets: +116.6R vs +105.4R, better in train/val and 2024 OOS; **hurts M5** — per-TF only) and `xau_strategy.blocked_regimes = ["trending"]` (mixed regime block: +65.7R vs +59.0R). A transitioning-SELL block was tested and REJECTED (bull-market artifact — failed 2024 OOS).
 - M15: `xau_strategy.sell_blocked_hours_utc = [15, 17]` (SELL-only hour block, validated 2026-07-16 on the 5-yr replay: +176.7R PF 1.31 vs +144.9R PF 1.22, better in all 6 years, both 12-mo halves, and 2024-06→2025-03 OOS; M5 cross-TF pocket confirms; BUYs at those hours are +34.3R so `blocked_hours_utc` would be wrong).
+- M15: `signals.trail_arm_r = 0.70` (trail arms later; validated 2026-07-21, 5-yr grid arm 0.3-0.9 × dist 0.5-1.0: +210.7R PF 1.35 WR 57.8% vs +175.7R PF 1.30 WR 53.9% at the 0.6 default; both halves and OOS better; 5yr max-DD clause 33.9R vs 29.1R waived by owner. Earlier-arm cells uniformly worse. M5 keeps 0.6).
 - The factory must stay equivalent to inline `PlatformConfig(symbol=XAUUSD, …)` + overrides — **enforced by a test in test_all.py**.
 
 ---
@@ -292,6 +293,7 @@ Replays history bar-by-bar through the **real `SignalAggregator.analyze_from_dat
 - Same-bar SL+TP tie → SL first (conservative). Gap through SL/TP → filled at the bar open.
 - **Trailing exits** (default on, from `signals.trail_arm_r/trail_dist_r`; XAU_PB trades carry per-trade 0.8/0.75 overrides): stop ratchets at bar close only, so a new stop can only fill from the next bar (conservative). Exit reasons: SL / TRAIL / TP1 (static mode) / TIMEOUT / NO_DATA.
 - Session + weekend + weekday filters evaluate the **decision time = bar close** (`ts + primary_duration`) — exactly matching the live bot's wall-clock check.
+- The optional H4-ADX regime filter (`config.backtest.regime_filter`, default off) is applied in the replay by calling the live `_apply_regime_filter_live` method itself under the same guard — live and backtest cannot diverge if it's enabled (2026-07-21 parity fix; the unregistered-pair config fallback also applies the config.json overlay now).
 - Confirmation TFs are sliced to bars **fully closed** by decision time (no look-ahead).
 
 **Performance:** `precompute_indicators` builds every indicator series once per TF (CuPy on GPU or NumPy — check the log line `Backend: CuPy GPU` vs `NumPy CPU fallback`; CuPy needs the `nvidia-*-cu12` pip wheels or it silently falls back). `GPUTechnicalEngine` subclasses the live engine and overrides only the `_compute_*` methods with cache lookups — outputs are byte-identical to the live engine (regression-tested). Bar replay: pure per-bar evaluation fans out over forked worker processes (`--workers`, 0 = auto: cores−2 capped 12; <5000 bars forces 1); the entry **cooldown (5 bars) is the only sequential rule**, applied in an ordered pass afterwards — parallel and sequential books are identical. ~300 bars/s/core, ~1700 bars/s at 10 workers.