Added idea way to fetch javadocs and sources.

2025/01/kotlin_demo1/.gitignore

@@ -1 +1,4 @@
 .gradle
+*.ipr
+*.iws
+.idea

2025/01/kotlin_demo1/build.gradle

@@ -1,4 +1,5 @@
 plugins {
+  id 'idea'
   id "org.jetbrains.kotlin.jvm" version "2.1.0"
 }
 
@@ -6,6 +7,13 @@ repositories {
   mavenCentral()
 }
 
+idea {
+  module {
+    downloadJavadoc = true
+    downloadSources = true
+  }
+}
+
 kotlin {
   jvmToolchain(17)
 }