feat(event): add CancellableLynxEvent

Author: TheRedMagic

content/docs/lynx/latest/modules/display/examples/custom-gui.mdx

@@ -126,11 +126,11 @@ Now that we have both the background and title done this is how it looks:
 
 ![Custom GUI Progress](https://cdn.undefinedcreations.com/lynx/display/custom-gui-progress.png)
 
-# Add Button Logic
+`# Add Button Logic
 
 Next step is adding the button logic. First step to this is creating the visual of the button.
 
-# Visual Logic
+### Visual Logic
 
 The button visual contains out of two entities, a `BlockDisplay` and `TextDisplay`. We will start by creating the `BlockDisplay`
 We will create it and then set the scale:
@@ -230,7 +230,7 @@ private fun addButton(location: Location) {
 }
 ```
 
-# Interaction
+### Interaction
 Now that the visual is done we will work of the interaction of the button.
 We will start by creating the `Interaction` entity and positioning it correctly:
 

content/docs/lynx/latest/modules/event/custom-event.mdx

@@ -51,7 +51,37 @@ class GameStateChangeEvent(
 ): LynxEvent() {}
 ```
 
-Now we have the custom event.
+## Cancellable Event
+
+If you want to make you event cancellable you need to change the extensions from `LynxEvent` to `CancellableLynxEvent`:
+
+```java tab="Java"
+public class GameStateChangeEvent extends CancellableLynxEvent {
+
+    private final GameState oldState;
+    private final GameState newState;
+
+    public GameStateChangeEvent(GameState oldState, GameState newState) {
+        this.oldState = oldState;
+        this.newState = newState;
+    }
+
+    public GameState getOldState() {
+        return oldState;
+    }
+
+    public GameState getNewState() {
+        return newState;
+    }
+
+}
+```
+```kotlin tab="Kotlin"
+class GameStateChangeEvent(
+    val oldState: GameState,
+    val newState: GameState
+): CancellableLynxEvent() {}
+```
 
 # Calling Events