fix(docs): clarify IntelliJ setup instructions (#122)

Closes: lightbend/kalix-docs#2253

docs/src/modules/java/pages/author-your-first-service.adoc

@@ -22,9 +22,22 @@ include::ROOT:partial$local-dev-prerequisites.adoc[]
 
 The Maven archetype template prompts you to specify the project's group ID, name and version interactively. Run it using the commands shown for your operating system.
 
-[sidebar]
-In IntelliJ, you can skip the command line. Open the IDE, select
-*File > New > Project*, and click to activate *Create from archetype*. Use the UI to locate the archetype and fill in the blanks.
+****
+If you are using IntelliJ, you can skip the command line entirely. Simply open the IDE and follow these steps:
+
+. Go to *File > New > Project*.
+. Select *Maven Archetype* from the list of Generators.
+. Fill out the project details:
+  * *Name*: Enter the desired project name, such as `helloworld`.
+  * *Location*: Specify the directory where you want the project to be created.
+  * *JDK*: Select Java {java-version} or a later version.
+. Under *Catalog*, ensure "Maven Central" is selected.
+. In the *Archetype* section, click the dropdown and select `io.akka:akka-javasdk-archetype`.
+. Set the *Version* to `{akka-javasdk-version}`.
+. Click *Create*.
+
+IntelliJ will handle the project generation and setup for you, allowing you to begin development immediately.
+****
 
 Follow these steps to generate and build your project: