Fix bare-metal Kura gateway scheduling so cache regions come online

Bare-metal cache regions (eu-central, us-east, us-west) failed to serve traffic because the regional gateway pods couldn’t schedule onto the cache nodes. The fix adds the matching toleration to the gateway pod template and manifest, so the host-network ingress-nginx gateway now schedules on the kura-dedibox box. As a result, the public cache endpoint is reachable and the dashboard no longer gets stuck at “Deploying” after a region cutover.