Implement basic structure for combat system and refactor code

Assets/Scripts/Meta/EntropyWallet.cs

@@ -0,0 +1,26 @@
+namespace KernelPanic.Meta
+{
+    /// <summary>
+    /// Tracks the player's persistent entropy currency balance.
+    /// </summary>
+    public sealed class EntropyWallet
+    {
+        public int Balance { get; private set; }
+
+        public void Add(int amount)
+        {
+            Balance += amount;
+        }
+
+        public bool Spend(int amount)
+        {
+            if (Balance < amount)
+            {
+                return false;
+            }
+
+            Balance -= amount;
+            return true;
+        }
+    }
+}

Assets/Scripts/Meta/EntropyWallet.cs.meta

@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: 8b77d0de67282ca4181a7c53feec4343

Assets/Scripts/Meta/GachaService.cs

@@ -0,0 +1,30 @@
+using System;
+
+namespace KernelPanic.Meta
+{
+    /// <summary>
+    /// Provides the contract for spending entropy on persistent unlock pulls.
+    /// </summary>
+    public sealed class GachaService
+    {
+        public GachaPullResult PerformPull(EntropyWallet wallet, int cost)
+        {
+            throw new NotImplementedException();
+        }
+    }
+
+    /// <summary>
+    /// Represents the result of a persistent unlock pull.
+    /// </summary>
+    public readonly struct GachaPullResult
+    {
+        public GachaPullResult(bool success, string unlockId)
+        {
+            Success = success;
+            UnlockId = unlockId;
+        }
+
+        public bool Success { get; }
+        public string UnlockId { get; }
+    }
+}

Assets/Scripts/Meta/GachaService.cs.meta

@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: f62e697e985a8a44ca26ccb8e853ee66

Assets/Scripts/Meta/SaveService.cs

@@ -0,0 +1,28 @@
+using System;
+
+namespace KernelPanic.Meta
+{
+    /// <summary>
+    /// Provides save and load contracts for persistent meta progression.
+    /// </summary>
+    public sealed class SaveService
+    {
+        public void Save(SaveData data)
+        {
+            throw new NotImplementedException();
+        }
+
+        public SaveData Load()
+        {
+            throw new NotImplementedException();
+        }
+    }
+
+    /// <summary>
+    /// Stores persistent progression data for serialization.
+    /// </summary>
+    public sealed class SaveData
+    {
+        public int EntropyBalance { get; set; }
+    }
+}

Assets/Scripts/Meta/SaveService.cs.meta

@@ -0,0 +1,2 @@
+fileFormatVersion: 2
+guid: 752a83f338afd024b8e728a1921e38ee