[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/Game/DiceManager.cs

@@ -10,22 +10,22 @@ namespace YachtDice.Game
         [SerializeField] private List<DiceRoller> diceRollers = new();
 
         public event Action OnAllDiceSettled;
-        public event Action<int, int> OnDieSettled;
+        public event Action<int, int> OnDiceSettled;
 
         public int DiceCount => diceRollers.Count;
 
-        private DieInstance[] diceInstances;
+        private DiceInstance[] diceInstances;
         private int pendingCount;
 
         private void Awake()
         {
             int count = diceRollers.Count;
-            diceInstances = new DieInstance[count];
+            diceInstances = new DiceInstance[count];
 
             for (int i = 0; i < count; i++)
             {
                 var definition = diceRollers[i].Definition;
-                diceInstances[i] = new DieInstance(definition);
+                diceInstances[i] = new DiceInstance(definition);
             }
         }
 
@@ -65,7 +65,7 @@ namespace YachtDice.Game
                 {
                     diceRollers[capturedIndex].OnRollFinished -= Handler;
                     diceInstances[capturedIndex].Value = value;
-                    OnDieSettled?.Invoke(capturedIndex, value);
+                    OnDiceSettled?.Invoke(capturedIndex, value);
 
                     pendingCount--;
                     if (pendingCount <= 0)
@@ -81,7 +81,7 @@ namespace YachtDice.Game
         }
 
         /// <summary>Возвращает абстрактный список дайсов (основной API).</summary>
-        public IReadOnlyList<IDie> GetDice() => diceInstances;
+        public IReadOnlyList<IDice> GetDice() => diceInstances;
 
         /// <summary>Возвращает копию текущих значений (обратная совместимость).</summary>
         public int[] GetCurrentValues()