hack/zagreb: Add description of hackathon

Signed-off-by: Stefan Jumarea <[email protected]>

content/hackathons/2024-05-zagreb/index.mdx

@@ -118,3 +118,9 @@ Mark the items as completed [here](https://docs.google.com/spreadsheets/d/1exnUC
 When porting new applications, you can run into issues both on the Docker build and on the Unikraft runtime.
 To debug the issues, you can follow the instructions [here](https://docs.kraft.cloud/guides/features/debugging/).
 Mark the items as completed [here](https://docs.google.com/spreadsheets/d/1exnUCaUvDx_FldLOz9HNnGpbmaafMYVL_0Tu6A6AFL4/edit#gid=680791461).
+
+### Hackathon
+
+For the hackathon, please create teams of 2-3 people, choose a project in any kind of language you like, using any applications you like, and deploy it on KraftCloud.
+At the and of the hackathon, you should make a PR in the [`catalog`](https://github.com/unikraft/catalog) repository with your work.
+We will be evaluating the project, focusing on functionality, originality, robustness, complexity, code quality and team work.