REFACTOR(app): remove ArgoCD integration

- Remove ArgoCD env vars (ARGOCD_SERVER_URL, ARGOCD_TOKEN, ARGOCD_CA_CERT)
- Delete SealedSecret files (dev/prod)
- Remove SealedSecret references from Kustomization
- App no longer calls ArgoCD API, settings not needed

deploy/k8s/base/deployment.yaml

@@ -30,20 +30,6 @@ spec:
           env:
             - name: NODE_ENV
               value: production
-            - name: ARGOCD_SERVER_URL
-              value: "https://argocd-server.argocd.svc.cluster.local"
-            - name: ARGOCD_TOKEN
-              valueFrom:
-                secretKeyRef:
-                  name: argocd-token
-                  key: token
-                  optional: false
-            - name: ARGOCD_CA_CERT
-              valueFrom:
-                secretKeyRef:
-                  name: argocd-ca-cert
-                  key: ca.crt
-                  optional: true
             - name: PROMETHEUS_URL
               value: "http://prometheus.monitoring.svc.cluster.local:9090"
           resources: