Added EntityToggleSitEvent

paper-api/src/main/java/io/papermc/paper/event/entity/EntityToggleSitEvent.java

@@ -0,0 +1,54 @@
+package io.papermc.paper.event.entity;
+
+import org.bukkit.entity.Entity;
+import org.bukkit.event.Cancellable;
+import org.bukkit.event.HandlerList;
+import org.bukkit.event.entity.EntityEvent;
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.NullMarked;
+
+/**
+ * Is called when an entity sits down or stands up.
+ */
+@NullMarked
+public class EntityToggleSitEvent extends EntityEvent implements Cancellable {
+
+    private static final HandlerList HANDLER_LIST = new HandlerList();
+
+    private final boolean isSitting;
+    private boolean cancelled;
+
+    @ApiStatus.Internal
+    public EntityToggleSitEvent(final Entity entity, final boolean isSitting) {
+        super(entity);
+        this.isSitting = isSitting;
+    }
+
+    /**
+     * Gets the new sitting state that the entity will change to.
+     *
+     * @return If it's going to sit or not.
+     */
+    public boolean getSittingState() {
+        return this.isSitting;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void setCancelled(final boolean cancel) {
+        this.cancelled = cancel;
+    }
+
+    @Override
+    public HandlerList getHandlers() {
+        return HANDLER_LIST;
+    }
+
+    public static HandlerList getHandlerList() {
+        return HANDLER_LIST;
+    }
+}