FEAT(repo): add config files for apps repo

- Add application.yaml for ArgoCD app-of-apps
- Add kustomization.yaml with all 8 application components
- Add renovate.json for automated updates

kustomization.yaml

@@ -0,0 +1,13 @@
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+resources:
+  - application.yaml
+  - gitea/argocd.yaml
+  - homer/argocd.yaml
+  - docusaurus/argocd.yaml
+  - code-server/argocd.yaml
+  - umami/argocd.yaml
+  - headlamp/argocd.yaml
+  - immich/argocd.yaml
+  - crafty/argocd.yaml