Add skybox switcher component

MapStation.Common/Runtime/MapOptions.cs

@@ -29,6 +29,10 @@ public class MapOption {
             public Camera PreviewCamera;
         }
 
+        private void Awake() {
+            _instance = this;
+        }
+
         public string GetDefaultOption(string optionName) {
             foreach(var option in Options) {
                 if (option.Name == optionName)

MapStation.Common/Runtime/SkyboxSwitcher.cs

@@ -0,0 +1,39 @@
+using Reptile;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using UnityEngine;
+
+namespace MapStation.Common.Runtime {
+    public class SkyboxSwitcher : MonoBehaviour {
+        [Header("Changes the skybox when enabled.")]
+        public Material Skybox;
+        private Material _oldSkybox;
+#if BEPINEX
+        private void Awake() {
+            StageManager.OnStageInitialized += StageInitialized;
+        }
+
+        private void OnDestroy() {
+            StageManager.OnStageInitialized -= StageInitialized;
+        }
+
+        private void StageInitialized() {
+            if (isActiveAndEnabled)
+                OnEnable();
+        }
+#endif
+
+        private void OnEnable() {
+            _oldSkybox = RenderSettings.skybox;
+            RenderSettings.skybox = Skybox;
+        }
+
+        private void OnDisable() {
+            if (RenderSettings.skybox == Skybox)
+                RenderSettings.skybox = _oldSkybox;
+        }
+    }
+}