FEAT(ci): add ArgoCD Image Updater and CI/CD pipelines

- ArgoCD Image Updater for Zot registry polling
- Tekton Tasks: git-clone, buildah-build-push
- Pipelines: nextjs, fastapi, python
- ExternalSecrets for Zot and GitHub credentials

tekton/ci-cd/manifests/secrets/zot-registry-secret.yaml

@@ -0,0 +1,27 @@
+apiVersion: external-secrets.io/v1
+kind: ExternalSecret
+metadata:
+  name: zot-registry-credentials
+  namespace: tekton-pipelines
+spec:
+  refreshInterval: 1h
+  secretStoreRef:
+    kind: ClusterSecretStore
+    name: vault-backend
+  target:
+    name: zot-registry-credentials
+    creationPolicy: Owner
+    template:
+      type: kubernetes.io/dockerconfigjson
+      data:
+        .dockerconfigjson: |
+          {"auths":{"zot0213.kro.kr":{"username":"{{ .USERNAME }}","password":"{{ .PASSWORD }}","auth":"{{ printf "%s:%s" .USERNAME .PASSWORD | b64enc }}"}}}
+  data:
+    - secretKey: USERNAME
+      remoteRef:
+        key: zot
+        property: USERNAME
+    - secretKey: PASSWORD
+      remoteRef:
+        key: zot
+        property: PASSWORD