fix(opencloud): reduce CPU request 250m→50m to free worker-2 slot for backup CronJob (DEV-594)

Worker-2 CPU requests were pinned at 100% (2000m/2000m), leaving no room
for the daily opencloud-backup CronJob (needs 20m). Actual opencloud CPU
usage is ~3m — reserving 250m was 80x over actual. Reduce to 50m which is
still 15x headroom. Frees 200m on worker-2.

Backup CronJob is pinned to the opencloud node by RWO PVC + hard
podAffinity. Reducing opencloud's own CPU request is the cleanest
unblock — contained to the opencloud namespace, no cross-app blast
radius.

Related: DEV-593, DEV-464, DEV-481, DEV-514, DEV-582/584 (recurring
pattern of backup CronJob squeezed off worker-2).

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/opencloud/opencloud-deployment.yaml

@@ -454,7 +454,7 @@ spec:
         resources:
           requests:
             memory: "512Mi"
-            cpu: "250m"
+            cpu: "50m"
           limits:
             memory: "2Gi"
             cpu: "1000m"