argocd: configure Telegram notifications and add Application manifests

- Configure argocd-notifications-cm with Telegram service, templates and triggers
  for sync-succeeded, sync-failed, and app-degraded events
- Add application-polymarket-bot.yaml and application-n8n.yaml with notification
  subscription annotations (chat_id: 5138407666)

Note: requires kubectl patch of argocd-notifications-secret with telegram-token

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

argocd/application-n8n.yaml

@@ -0,0 +1,24 @@
+apiVersion: argoproj.io/v1alpha1
+kind: Application
+metadata:
+  name: n8n
+  namespace: argocd
+  annotations:
+    notifications.argoproj.io/subscribe.on-sync-succeeded.telegram: "5138407666"
+    notifications.argoproj.io/subscribe.on-sync-failed.telegram: "5138407666"
+    notifications.argoproj.io/subscribe.on-degraded.telegram: "5138407666"
+spec:
+  project: default
+  source:
+    repoURL: http://gitea.gitea.svc.cluster.local:3000/chemavx/k8s-manifests.git
+    targetRevision: main
+    path: n8n
+  destination:
+    server: https://kubernetes.default.svc
+    namespace: n8n
+  syncPolicy:
+    automated:
+      prune: true
+      selfHeal: true
+    syncOptions:
+      - CreateNamespace=true