Document the need for a case sensitive FS

CONTRIBUTING.md

@@ -222,6 +222,10 @@ in [`native-tests.json`](.github/native-tests.json) to have its integration test
 
 If you have not done so on this machine, you need to:
 
+* Make sure you have a case-sensitive filesystem. Java development on a case-insensitive filesystem can cause headaches.
+    * Linux: You're good to go.
+    * macOS: Use the `Disk Utility.app` to check. It also allows you to create a case-sensitive volume to store your code projects. See this [blog entry](https://karnsonline.com/case-sensitive-apfs/) for more.
+    * Windows: [Enable case sensitive file names per directory](https://learn.microsoft.com/en-us/windows/wsl/case-sensitivity)
 * Install Git and configure your GitHub access
 * Install Java SDK 11+ (OpenJDK recommended)
 * Install [GraalVM](https://quarkus.io/guides/building-native-image)