feat(combat): metamagic

src/pf1e_simulator/dice.py

@@ -80,10 +80,12 @@ class DiceExpr(BaseModel):
 
     def mean(self) -> float:
         """Expected value: count * (sides + 1) / 2 + bonus."""
-        if self.count == 0:
-            return float(self.bonus)
         return self.count * (self.sides + 1) / 2 + self.bonus
 
+    def max_value(self) -> int:
+        """Maximum possible value: count * sides + bonus."""
+        return self.count * self.sides + self.bonus
+
 
 def parse_dice(text: str) -> DiceExpr:
     """Parse a dice notation string into a DiceExpr.