feat(backup-system): migración completa a GitOps

- CronJob rclone-mega-backup entra en git (solo existía imperativo)
- Scripts backup.sh/verify.sh/rclone-mega.sh como ConfigMap backup-scripts
  (antes hostPath /data/backups/scripts — cambios ahora pasan por git+ArgoCD)
- rclone.conf vía InfisicalStaticSecret (homelab/prod//backup-system → RCLONE_CONF),
  sustituye al hostPath de ~/.config/rclone/rclone.conf
- Imágenes pinneadas: rclone 1.74.3, bitnami/kubectl por digest (v1.36.2)
- ClusterRole/CRB de backup-sa entran en git
- Application ArgoCD backup-system (auto-sync + prune + selfHeal)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

backup-system/cronjob-rclone-mega.yaml

@@ -0,0 +1,52 @@
+apiVersion: batch/v1
+kind: CronJob
+metadata:
+  name: rclone-mega-backup
+  namespace: backup-system
+spec:
+  schedule: "0 3 * * 0"
+  concurrencyPolicy: Forbid
+  failedJobsHistoryLimit: 2
+  successfulJobsHistoryLimit: 3
+  jobTemplate:
+    spec:
+      template:
+        spec:
+          nodeSelector:
+            kubernetes.io/hostname: chemavx-k8
+          restartPolicy: OnFailure
+          securityContext:
+            runAsUser: 0
+          containers:
+            - name: rclone
+              image: docker.io/rclone/rclone:1.74.3
+              command: ["/bin/sh", "/scripts/rclone-mega.sh"]
+              resources:
+                requests:
+                  cpu: 100m
+                  memory: 128Mi
+                limits:
+                  cpu: 500m
+                  memory: 512Mi
+              volumeMounts:
+                - mountPath: /data/backups/backups
+                  name: backup-dir
+                - mountPath: /rclone
+                  name: rclone-conf
+                - mountPath: /scripts
+                  name: scripts
+          volumes:
+            - name: backup-dir
+              hostPath:
+                path: /data/backups/backups
+                type: DirectoryOrCreate
+            - name: rclone-conf
+              secret:
+                secretName: rclone-conf-infisical
+                items:
+                  - key: RCLONE_CONF
+                    path: rclone.conf
+            - name: scripts
+              configMap:
+                name: backup-scripts
+                defaultMode: 0755