[Rename] Unify Die → Dice naming across the entire project

Standardize all class, interface, file, method, event, field, and variable
names from the inconsistent "Die" form to "Dice", matching the existing
DiceManager/DiceCatalog/DiceCollection convention.

Renamed files (7 + meta): IDie→IDice, DieInstance→DiceInstance,
DieDefinitionSO→DiceDefinitionSO, StandardDieSO→StandardDiceSO,
DieValueCondition→DiceValueCondition, AddPerDieEffect→AddPerDiceEffect,
MultiplyPerDieEffect→MultiplyPerDiceEffect.

Updated all 31 consumer and test files with matching reference changes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Assets/Scripts/Modifiers/Conditions/DiceCountCondition.cs

@@ -8,7 +8,7 @@ namespace YachtDice.Modifiers.Conditions
     [CreateAssetMenu(fileName = "DiceCountCondition", menuName = "YachtDice/Modifiers/Conditions/Dice Count")]
     public class DiceCountCondition : Condition
     {
-        [Tooltip("Die face value to count (1-6). 0 = any value.")]
+        [Tooltip("Dice face value to count (1-6). 0 = any value.")]
         [SerializeField, Range(0, 6)] private int targetValue;
 
         [Tooltip("Minimum number of dice that must match.")]

Assets/Scripts/Modifiers/Conditions/DiceValueCondition.cs

@@ -5,8 +5,8 @@ using YachtDice.Modifiers.Runtime;
 
 namespace YachtDice.Modifiers.Conditions
 {
-    [CreateAssetMenu(fileName = "DieValueCondition", menuName = "YachtDice/Modifiers/Conditions/Die Value")]
-    public class DieValueCondition : Condition
+    [CreateAssetMenu(fileName = "DiceValueCondition", menuName = "YachtDice/Modifiers/Conditions/Dice Value")]
+    public class DiceValueCondition : Condition
     {
         [SerializeField, Range(1, 6)] private int targetValue = 1;
         [SerializeField] private int minCount = 1;
@@ -25,9 +25,9 @@ namespace YachtDice.Modifiers.Conditions
         }
 
 #if UNITY_EDITOR
-        public static DieValueCondition CreateForTest(int targetValue, int minCount = 1)
+        public static DiceValueCondition CreateForTest(int targetValue, int minCount = 1)
         {
-            var so = CreateInstance<DieValueCondition>();
+            var so = CreateInstance<DiceValueCondition>();
             so.targetValue = targetValue;
             so.minCount = minCount;
             return so;