Add documentation for preview deployment workflow

Co-authored-by: commjoen <[email protected]>

Author: Copilot

CONTRIBUTING.md

@@ -46,6 +46,37 @@ Pull requests should be as small/atomic as possible. Large, wide-sweeping change
 
   For example: `Fix #545` or `Closes #10`
 
+### Testing your changes with Preview Deployments
+
+When you create a pull request, GitHub Actions will automatically build and publish preview Docker containers to GitHub Container Registry. This allows you and reviewers to easily test your changes before merging.
+
+#### How Preview Deployments Work
+
+1. **Automatic Build**: When you open a PR, the preview workflow builds both `wrongsecrets-balancer` and `cleaner` containers
+2. **Container Publishing**: Images are pushed to `ghcr.io` with PR-specific tags (e.g., `pr-123`)
+3. **Deployment Instructions**: A comment is automatically posted on your PR with detailed deployment instructions
+4. **Easy Testing**: Anyone can deploy and test your changes using the provided Helm commands
+
+#### Using Preview Deployments
+
+After opening a PR, look for the automated comment that provides:
+
+- **Direct deployment commands** using Helm
+- **Custom values file** for advanced configuration
+- **Container registry links** to inspect the built images
+- **Local testing instructions** for different deployment scenarios
+
+Example deployment command from the preview comment:
+```bash
+helm install my-preview wrongsecrets/wrongsecrets-ctf-party \
+  --set balancer.repository=ghcr.io/owasp/wrongsecrets-balancer \
+  --set balancer.tag=pr-123 \
+  --set wrongsecretsCleanup.repository=ghcr.io/owasp/cleaner \
+  --set wrongsecretsCleanup.tag=pr-123
+```
+
+This makes it easy for maintainers and other contributors to test your changes in a real Kubernetes environment.
+
 ## How to set up your Contributor Environment
 
 1. Create a GitHub account. Multiple different GitHub subscription plans are available, but you only need a free one. Follow [these steps](https://help.github.com/en/articles/signing-up-for-a-new-github-account "Signing up for a new GitHub account") to set up your account.

readme.md

@@ -68,6 +68,8 @@ A 100 contestant game can be played on the AWS, GCP, and Azure setup, which will
 
 This is an experimental release. It showed to work at 6 CTFs already, we just did not complete the documentation and the cleaning up of the Helm chart yet. However: it is working in its basis, and can support a good crowd. Currently, we support using Minikube, AWS EKS, GCP GKE, and Azure AKS (_**Please follow the readme in the folder for each cloud provider if you want to use it, as the guides section is not updated yet**_).
 
+**For Contributors**: Pull requests automatically generate preview deployments with containers published to GitHub Container Registry. See the automated PR comments for deployment instructions.
+
 ## How to use it
 
 The different setups are explained in [OWASP WrongSecrets CTF-instructions](https://github.com/OWASP/wrongsecrets/blob/master/ctf-instructions.md). With the 3-domain approach you generate flags for CTFD automatically, while with the 2-domain setup you need to set it up manually.