REFACTOR(app): migrate to argocd

- Add Kustomize base and prod overlay structure
- Optimize resources for 2GB RAM environment (100Mi/200Mi)
- Add ArgoCD Application manifest
- Remove old k8s manifests (replaced by Kustomize)
- Add comprehensive deployment guide

deploy/k8s/overlays/prod/kustomization.yaml

@@ -0,0 +1,18 @@
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+
+namespace: jovies
+
+resources:
+  - ../../base
+
+commonLabels:
+  environment: production
+
+# 이미지 태그 설정
+images:
+  - name: ghcr.io/mayne0213/jovies
+    newTag: latest
+
+patchesStrategicMerge:
+  - deployment-patch.yaml