Trigger book: mega-gapper squeeze exception (the LHSW/NXTS fix)

LHSW gapped +278% on 100M shares, was rank 2 in the trigger book at
4:49am, ran +346%, and was the source trader's entire day — the bot's
TRIGGER_GAP_MAX=35 capped it out, same as NXTS two weeks ago, while the
bot spent its entries on the shadow round-trips (SEER/ELAB/PLUG/YRD).

Year-scale replay (n=2,879 ORB entries, 14 months, reverse-split
artifacts excluded by requiring a real volume surge): the 35-150% band
is dead (+0.02R / +0.00R — the cap earns its keep there), but REAL
>150% squeezes (n=82) ran +0.63R with 8/14 months >= 0, 4x the core
band's edge. New gap_squeeze_min/gap_squeeze_rvol re-admit gaps >=150%
only when rvol >= 5 (split repricings show rvol ~0.01 and stay out).
Live: TRIGGER_GAP_SQUEEZE_MIN=150, TRIGGER_GAP_SQUEEZE_RVOL=5.0.
Existing guards (trigger/day extension, halt, BE@+5% ratchet, sizing)
still apply to these names.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/unit/test_triggers.py

@@ -363,3 +363,26 @@ def test_guard_grace_window_protects_just_armed_entry():
                         "armed_at": datetime.now(), "checks": 0}  # armed just now
     assert svc.expire_stale_entries() == []     # grace -> not cancelled
     assert "o1" in svc._armed and client.canceled == []
+
+
+def test_gap_cap_blocks_mid_band_but_squeeze_exception_readmits_real_monsters():
+    """2026-07-06 (LHSW +278%, the trader's only real profit, capped out at 4:49am):
+    gap_max still blocks the dead 35-150% band, but a REAL mega-gapper — huge gap
+    AND a genuine volume surge — re-arms via the squeeze exception. A reverse-split
+    repricing (huge "gap", no volume) must stay excluded."""
+    b = ArmedTriggerBook(gap_min=10, gap_max=35, gap_squeeze_min=150,
+                         gap_squeeze_rvol=5.0, rvol_min=2)
+    b.arm([
+        _cand("MID", gap=80.0, rvol=20.0),     # dead band: capped
+        _cand("LHSW", gap=278.0, rvol=40.0),   # real monster: admitted
+        _cand("SPLIT", gap=278.0, rvol=0.4),   # reverse-split fake: excluded
+    ])
+    assert b.triggers["MID"].state == WEAK
+    assert b.triggers["LHSW"].state == ARMED
+    assert b.triggers["SPLIT"].state == WEAK
+
+
+def test_squeeze_exception_off_by_default():
+    b = ArmedTriggerBook(gap_min=10, gap_max=35, rvol_min=2)
+    b.arm([_cand("LHSW", gap=278.0, rvol=40.0)])
+    assert b.triggers["LHSW"].state == WEAK