ci(argocd): watch deploy branch for kustomization updates

targetRevision changed from master to deploy so Argo CD tracks the
image-tag commits the CI bot writes there, not the source branch.

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

argocd/application.yaml

@@ -7,7 +7,7 @@ spec:
   project: default
   source:
     repoURL: https://git.aleshym.co/funman300/Ferrous-Solitaire.git
-    targetRevision: master
+    targetRevision: deploy
     path: deploy
   destination:
     server: https://kubernetes.default.svc