CHORE(deploy): use argocd for kaniko

Infrastructure as Code:
- Add Kaniko namespace and RBAC manifests
- Create ArgoCD Application for Kaniko infrastructure
- Kustomize configuration for Kaniko resources

Workflow improvements:
- Remove kubeconfig dependency
- Use in-cluster ServiceAccount (runner runs in K8s)
- Remove all sudo commands
- Simplify Kubernetes access

GitOps workflow:
1. Push manifests to Git
2. ArgoCD auto-syncs infrastructure
3. Gitea runner uses ServiceAccount permissions
4. Kaniko builds run in kaniko-builds namespace

Benefits:
- True GitOps approach
- No secrets management needed
- Declarative infrastructure
- ArgoCD handles reconciliation
- Audit trail in Git

deploy/argocd/application-kaniko-infra.yaml

@@ -0,0 +1,29 @@
+apiVersion: argoproj.io/v1alpha1
+kind: Application
+metadata:
+  name: kaniko-infrastructure
+  namespace: argocd
+  finalizers:
+    - resources-finalizer.argocd.argoproj.io
+spec:
+  project: default
+  source:
+    repoURL: https://gitea0213.kro.kr/bluemayne/jovies.git
+    targetRevision: main
+    path: deploy/kaniko
+  destination:
+    server: https://kubernetes.default.svc
+    namespace: kaniko-builds
+  syncPolicy:
+    automated:
+      prune: true
+      selfHeal: true
+      allowEmpty: false
+    syncOptions:
+      - CreateNamespace=true
+    retry:
+      limit: 5
+      backoff:
+        duration: 5s
+        factor: 2
+        maxDuration: 3m