Added esc exit feature.

Runtime/EscExit.cs

@@ -0,0 +1,21 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class EscExit : MonoBehaviour
+{
+    // Start is called before the first frame update
+    void Start()
+    {
+        
+    }
+
+    // Update is called once per frame
+    void Update()
+    {
+        if (Input.GetKeyDown(KeyCode.Escape))
+        {
+            Application.Quit();
+        }
+    }
+}

Runtime/EscExit.cs.meta

@@ -0,0 +1,11 @@
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