Automatic holiday sprites (#22929)

Content.Client/Holiday/HolidayRsiSwapComponent.cs

@@ -0,0 +1,14 @@
+namespace Content.Client.Holiday;
+
+/// <summary>
+/// This is used for a component that swaps an entity's RSI based on HolidayVisuals
+/// </summary>
+[RegisterComponent]
+public sealed partial class HolidayRsiSwapComponent : Component
+{
+    /// <summary>
+    /// A dictionary of arbitrary visual keys to an rsi to swap the sprite to.
+    /// </summary>
+    [DataField]
+    public Dictionary<string, string> Sprite = new();
+}