fix(rules): combat maneuvers auto-succeed (natural 20) vs incapacitated targets

src/pf1e_simulator/combat.py

@@ -4641,6 +4641,15 @@ class CombatEngine:
         attacker_cmb = self._maneuver_cmb(state) - pa_amt - grapple_penalty
         target_cmd = self._maneuver_cmd(target)
         roll = self._rng.d20()
+        # PF1e (SRD Combat Maneuvers): "If your target is immobilized,
+        # unconscious, or otherwise incapacitated, your maneuver
+        # automatically succeeds (treat as if you rolled a natural 20 on
+        # the attack roll)." The engine's incapacitated notion is the
+        # helpless set (helpless/paralyzed/asleep/unconscious, CRB
+        # "Conditions"); the natural 20 also feeds the margin-based
+        # outcomes (bull rush / overrun / reposition / drag / dirty trick).
+        if self._is_helpless(target):
+            roll = _NATURAL_TWENTY
         # PF1e (CRB Combat Maneuvers): the provoked-AoO damage rides the
         # check total (floored at 0); natural 20/1 keep their rules below.
         total = max(0, roll + attacker_cmb - aoo_damage)