tuned: fewer warnings in IntelliJ IDEA;

--- a/src/Pure/Concurrent/event_timer.scala	Sun Dec 22 14:11:31 2024 +0100
+++ b/src/Pure/Concurrent/event_timer.scala	Sun Dec 22 14:13:21 2024 +0100
@@ -25,7 +25,7 @@
   }
 
   def request(time: Time, repeat: Option[Time] = None)(event: => Unit): Request = {
-    val task = new TimerTask { def run: Unit = event }
+    val task = new TimerTask { def run(): Unit = event }
     repeat match {
       case None => event_timer.schedule(task, new JDate(time.ms))
       case Some(rep) => event_timer.schedule(task, new JDate(time.ms), rep.ms)

--- a/src/Pure/System/isabelle_system.scala	Sun Dec 22 14:11:31 2024 +0100
+++ b/src/Pure/System/isabelle_system.scala	Sun Dec 22 14:13:21 2024 +0100
@@ -390,7 +390,7 @@
   /* JVM shutdown hook */
 
   def create_shutdown_hook(body: => Unit): Thread = {
-    val shutdown_hook = Isabelle_Thread.create(new Runnable { def run: Unit = body })
+    val shutdown_hook = Isabelle_Thread.create(new Runnable { def run(): Unit = body })
 
     try { Runtime.getRuntime.addShutdownHook(shutdown_hook) }
     catch { case _: IllegalStateException => }