Build system changes

paper-api/src/main/java/io/papermc/paper/annotation/DoNotUse.java

@@ -0,0 +1,18 @@
+package io.papermc.paper.annotation;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+import org.jetbrains.annotations.ApiStatus;
+
+/**
+ * Annotation used to mark methods or constructors which should not be called.
+ *
+ * <p>Separate from {@link Deprecated} to differentiate from the large amount of deprecations.</p>
+ */
+@ApiStatus.Internal
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ElementType.METHOD, ElementType.CONSTRUCTOR})
+public @interface DoNotUse {
+}