add retention and target and change the annotation parameter to "value" for easier usage

lib/src/main/java/net/tomatentum/marinara/interaction/annotation/Button.java

@@ -1,5 +1,12 @@
 package net.tomatentum.marinara.interaction.annotation;
 
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target({ElementType.METHOD})
+@Retention(RetentionPolicy.RUNTIME)
 public @interface Button {
-    public String customId();
+    public String value(); //aka customId
 }

lib/src/main/java/net/tomatentum/marinara/interaction/methods/ButtonInteractionMethod.java

@@ -34,7 +34,7 @@ public class ButtonInteractionMethod extends InteractionMethod {
 
     private void parseMethod() {
         Button button = getMethod().getAnnotation(Button.class);
-        this.customId = button.customId();
+        this.customId = button.value();
     }
     
 }