configure java version and main class in gradle

build.gradle.kts

@@ -1,5 +1,16 @@
 plugins {
     id("java")
+    id("application")
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(22)
+    }
+}
+
+application {
+    mainClass = "eu.jonahbauer.raytracing.Main"
 }
 
 dependencies {