feat: add GitOps structure for kubernetes-dashboard, n8n, xslt-lab

- apps/kubernetes-dashboard: raw manifests (namespace, rbac, deployment, service, ingress)
- apps/n8n: Helm values referencing existing n8n-postgresql secret (no password in git)
- apps/xslt-lab: Helm values for xslt-playground chart
- argocd/applications: ArgoCD Application CRDs for all three apps

apps/kubernetes-dashboard/ingress.yaml

@@ -0,0 +1,24 @@
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: kubernetes-dashboard
+  namespace: kubernetes-dashboard
+  annotations:
+    nginx.ingress.kubernetes.io/backend-protocol: HTTPS
+spec:
+  ingressClassName: public
+  rules:
+  - host: k8s.alexandre-vazquez.internal
+    http:
+      paths:
+      - path: /
+        pathType: Prefix
+        backend:
+          service:
+            name: kubernetes-dashboard
+            port:
+              number: 443
+  tls:
+  - hosts:
+    - k8s.alexandre-vazquez.internal
+    secretName: k8s-dashboard-tls