fix(platform): fix high-restart pods - prometheus nodeSelector, litellm resources, gitea-runner limits

- Prometheus: change nodeSelector from hardware=high-memory (nonexistent label) to kubernetes.io/arch: amd64
  Fixes OOMKilled cause - pod was being scheduled on wrong nodes.
- litellm-deployment: add resource limits (2Gi/500m requests, 4Gi/2000m limits) + pin image to v1.34.0
  Fixes OOMKilled cause - no resource limits were set.
- gitea-runner: pin image to v0.12.0 from :latest + add resource limits (512Mi/250m requests, 1Gi/500m limits)
  Addresses extreme restart count (281) caused by unbounded memory usage and rolling image updates.

gitea/gitea.yaml

@@ -119,7 +119,14 @@ spec:
         kubernetes.io/arch: arm64
       containers:
       - name: gitea-runner
-        image: vegardit/gitea-act-runner:latest
+        image: vegardit/gitea-act-runner:v0.12.0
+        resources:
+          requests:
+            memory: "512Mi"
+            cpu: "250m"
+          limits:
+            memory: "1Gi"
+            cpu: "500m"
         env:
         - name: GITEA_INSTANCE_URL
           valueFrom:

monitoring/prometheus-deployment.yaml

@@ -15,9 +15,10 @@ spec:
       labels:
         app: prometheus
     spec:
-      # Prevent scheduling on Raspberry Pi due to resource requirements (512Mi-1Gi memory, 500m-1000m CPU)
+      # Target the nucbox (amd64, 24Gi RAM) which is the only node with enough memory for Prometheus.
       nodeSelector:
-        hardware: high-memory
+        kubernetes.io/os: linux
+        kubernetes.io/arch: amd64
       serviceAccountName: prometheus
       containers:
         - name: prometheus