fix(rules): any concealment denies sneak attack (SRD rogue: 'a creature with concealment')

src/pf1e_simulator/combat.py

@@ -2999,14 +2999,15 @@ class CombatEngine:
 
         PF1e: precision damage when the target is flanked (melee only, melee
         touch included) or denied its Dex bonus to AC (melee, or ranged within
-        30 ft); dice = (level + 1) // 2. Only TOTAL concealment (miss chance
-        >= 50%) denies the sneak attack; partial concealment (blurred 20%)
-        does not (CRB rogue "Sneak Attack": "cannot sneak attack while
-        striking a creature with total concealment"). A BLINDED attacker faces
-        total concealment against ALL its opponents (CRB "Conditions —
-        Blinded": "All opponents are considered to have total concealment
-        (50% miss chance) against the blinded character"), so it cannot sneak
-        attack either — same max(target, 50) convention as _resolve_hit_damage.
+        30 ft); dice = (level + 1) // 2. ANY concealment (miss chance > 0)
+        denies the sneak attack (SRD rogue "Sneak Attack": "A rogue cannot
+        sneak attack while striking a creature with concealment" — the rogue
+        must see the target well enough to pick a vital spot). A BLINDED
+        attacker faces total concealment against ALL its opponents (CRB
+        "Conditions — Blinded": "All opponents are considered to have total
+        concealment (50% miss chance) against the blinded character"), so it
+        cannot sneak attack either — same max(target, 50) convention as
+        _resolve_hit_damage.
         PF1e (CRB): undead and constructs are immune to precision damage —
         ooze/plant immunity is not modeled (no such creature types exist in
         the data model).
@@ -3015,7 +3016,7 @@ class CombatEngine:
         if self._has_condition_named(attacker, "blinded"):
             effective_concealment = max(concealment, _TOTAL_CONCEALMENT_PCT)
         if (
-            effective_concealment >= _TOTAL_CONCEALMENT_PCT
+            effective_concealment > 0
             or not self._has_feat(attacker, _SNEAK_ATTACK_FEATURE)
         ):
             return 0