Begin work on outlining dynamic side

PkmnLib.Dynamic/Models/BattleResult.cs

@@ -0,0 +1,23 @@
+namespace PkmnLib.Dynamic.Models;
+
+public record struct BattleResult
+{
+    private BattleResult(bool conclusiveResult, byte? winningSide)
+    {
+        ConclusiveResult = conclusiveResult;
+        WinningSide = winningSide;
+    }
+    
+    public static BattleResult Inconclusive => new(false, null);
+    public static BattleResult Conclusive(byte winningSide) => new(true, winningSide);
+    
+    /// <summary>
+    /// Whether the battle has a conclusive result. If false, no side has won.
+    /// </summary>
+    public bool ConclusiveResult { get; }
+    
+    /// <summary>
+    /// The side that won the battle. If null, no side has won.
+    /// </summary>
+    public byte? WinningSide { get; }
+}