runners: scale DM/AiStation.Linux/WorldBuilder down to 1 replica until cluster relieved

After cutting requests to 100m, 4 of 6 new pods scheduled and 2 stayed
Pending — cluster CPU REQUEST utilization is 49.6 of 48 allocatable cores
because the existing fleet of ~50 idle runners reserves 25.6 cores
(500m × ~50) for ~50m actual use. Single-replica per new repo gets the
service online without competing with in-flight CI from the rest of the
fleet.

When the broader fleet-wide request right-sizing pass lands
(500m → 100m on all idle runners would free ~20 cores), these can be
bumped back to 2 replicas if PR-CI backlog warrants it.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/github-runner/github-runner.yaml

@@ -4189,7 +4189,9 @@ metadata:
     flowercore.io/runner-repo: device-management
     flowercore.io/github-repo: FlowerCore.DeviceManagement
 spec:
-  replicas: 2
+  # Single replica until cluster CPU pressure resolves; the fleet-wide
+  # request right-sizing pass is queued for a future sweep.
+  replicas: 1
   selector:
     matchLabels:
       app.kubernetes.io/name: github-runner-device-management
@@ -4326,7 +4328,9 @@ metadata:
     flowercore.io/runner-repo: aistation-linux
     flowercore.io/github-repo: FlowerCore.AiStation.Linux
 spec:
-  replicas: 2
+  # Single replica until cluster CPU pressure resolves; the fleet-wide
+  # request right-sizing pass is queued for a future sweep.
+  replicas: 1
   selector:
     matchLabels:
       app.kubernetes.io/name: github-runner-aistation-linux
@@ -4459,7 +4463,9 @@ metadata:
     flowercore.io/runner-repo: worldbuilder
     flowercore.io/github-repo: FlowerCore.WorldBuilder
 spec:
-  replicas: 2
+  # Single replica until cluster CPU pressure resolves; the fleet-wide
+  # request right-sizing pass is queued for a future sweep.
+  replicas: 1
   selector:
     matchLabels:
       app.kubernetes.io/name: github-runner-worldbuilder