fix: trigger fires require a fresh cross — stale breaks after a blind window are chases

SNXX 2026-07-21: 18s after a mid-morning restart the fast path bought a
15-minute-old break +1.6% above the trigger — fires() only checked
price >= trigger, so any blind window (boot, halt, feed outage) fired
instantly on already-extended moves. A trigger now fires only if the live
price was seen BELOW the trigger since arming (a real cross), with a
small at-the-break tolerance (TRIGGER_FRESH_CROSS_TOL, default 1.5%)
so a fast break between ticks still fires; beyond it the name must pull
back below the level and re-cross. Gap-through runners stay covered by
the slow marketable path.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

runtime/triggers.py

@@ -73,6 +73,12 @@ class ArmedTrigger:
     day_open: float | None = None  # session-open price (for the day-extension gate)
     state: str = WAITING
     rank: int = 0
+    # live price has been observed BELOW the trigger since arming — a fire is a
+    # fresh CROSS, not "price happens to stand above the level". Without this,
+    # any blind window (boot after a blocked spell, halt, feed outage) fires
+    # instantly on stale, already-extended breaks (SNXX 2026-07-21: bought a
+    # 15-min-old break +1.6% above trigger 18s after restart).
+    seen_below: bool = False
 
     def distance_pct(self) -> float | None:
         """How far live price is from the trigger, as a fraction.
@@ -126,6 +132,11 @@ class ArmedTriggerBook:
     # would otherwise let a name fire on a frozen quote into a reverted market.
     # 0 = off.
     max_price_age_s: float = 0.0
+    # fire without a seen-below cross only within this fraction ABOVE the trigger
+    # ("at the break" tolerance). Beyond it, require a pullback below the trigger
+    # and a fresh re-cross — stale breaks discovered after a blind window are not
+    # entries, they're chases. 0 = always require the cross.
+    fresh_cross_tol: float = 0.015
     triggers: dict[str, ArmedTrigger] = field(default_factory=dict)
     _lock: object = field(default_factory=threading.RLock, repr=False, compare=False)
 
@@ -209,6 +220,8 @@ class ArmedTriggerBook:
         else:
             t.price = float(price)
             t.price_ts = time.monotonic()
+            if t.trigger is not None and t.price < t.trigger:
+                t.seen_below = True
 
     @_synced
     def fires(self) -> list[ArmedTrigger]:
@@ -223,6 +236,8 @@ class ArmedTriggerBook:
             and t.price is not None
             and t.trigger is not None
             and t.price >= t.trigger
+            and (t.seen_below
+                 or t.price <= t.trigger * (1.0 + self.fresh_cross_tol))
             and (max_age <= 0 or (now - t.price_ts) <= max_age)
         ]