feat(content): laod example-apps via content-loader functionality

- Move example-app definitions from `argocd/example-apps` and `applications/` into `examples/example-apps-via-content-loader`
- Adjust Dockerfile to initialize example-apps folder as standalone git repo for content-loader
- Update `GitopsPlaygroundCli` to include content examples via `--content.examples` flag
- Extend config merging logic (`MapUtils.deepMerge`) to support additional example content source
- Update schema, configurator, and tests to handle example-apps path and validation
- Clean up redundant templates and adjust paths accordingly

This refactor isolates example application definitions into a dedicated content-loader directory,
simplifying configuration handling and enabling dynamic content loading via the CLI.

Author: pmarkiewka

.dockerignore

@@ -3,6 +3,7 @@
 
 # Allowlist
 !applications/
+!examples/
 !exercises/
 !argocd/
 !docker-registry/

Dockerfile

@@ -218,7 +218,8 @@ ENV HOME=/home \
     GITOPS_BUILD_LIB_REPO=/gitops/repos/gitops-build-lib.git \
     CES_BUILD_LIB_REPO=/gitops/repos/ces-build-lib.git \
     JENKINS_PLUGIN_FOLDER=/gitops/jenkins-plugins/ \
-    LOCAL_HELM_CHART_FOLDER=/gitops/charts/
+    LOCAL_HELM_CHART_FOLDER=/gitops/charts/ \
+    EXAMPLE_APPS_CONTENT_REPO=/app/examples/example-apps-via-content-loader
 
 WORKDIR /app
 
@@ -232,10 +233,30 @@ RUN apk update --no-cache && apk upgrade --no-cache && \
      git \
     unzip
 
-USER 1000:0
-
 COPY --from=downloader /dist /
 
+# Set example apps config to use the repos from the image
+RUN sed -i \
+  -e "s|url: https://github.com/cloudogu/gitops-build-lib|url: 'file://$GITOPS_BUILD_LIB_REPO'|g" \
+  -e "s|url: https://github.com/cloudogu/ces-build-lib|url: 'file://$CES_BUILD_LIB_REPO'|g" \
+  -e "s|url: https://github.com/cloudogu/spring-boot-helm-chart|url: 'file://$SPRING_BOOT_HELM_CHART_REPO'|g" \
+  -e "s|url: https://github.com/cloudogu/spring-petclinic|url: 'file://$SPRING_PETCLINIC_REPO'|g" \
+  -e "s|url: https://github.com/cloudogu/gitops-playground|url: 'file://$EXAMPLE_APPS_CONTENT_REPO'|g" \
+  -e "/^[[:space:]]*path: examples\/example-apps-via-content-loader\//d" \
+  /app/examples/example-apps-via-content-loader/config.yaml
+
+# Initialize example apps folder with git, so we can use it with content-loader
+# we need safe.directory setting because of: fatal: detected dubious ownership in repository at '/app/examples/example-apps-via-content-loader'
+RUN git -C /app/examples/example-apps-via-content-loader init -b main && \
+    git -C /app/examples/example-apps-via-content-loader config user.email "noreply@example.com" && \
+    git -C /app/examples/example-apps-via-content-loader config user.name "Container" && \
+    git -C /app/examples/example-apps-via-content-loader add -A && \
+    git -C /app/examples/example-apps-via-content-loader commit -m "initial commit" && \
+    git config --global --add safe.directory /app/examples/example-apps-via-content-loader
+
+
+USER 1000:0
+
 ARG VCS_REF
 ARG BUILD_DATE
 LABEL org.opencontainers.image.title="gitops-playground" \