CHORE(app): reduce resource limits

- CPU limit: 800m → 100m (prod), 560m → 80m (dev)
- Memory limit: 230Mi → 150Mi (prod), 161Mi → 120Mi (dev)
- ResourceQuota adjusted accordingly

Actual usage: ~8m CPU, ~111Mi memory

deploy/k8s/overlays/prod/resourcequota.yaml

@@ -5,8 +5,8 @@ metadata:
   namespace: portfolio
 spec:
   hard:
-    requests.memory: "750Mi"
-    requests.cpu: "1200m"
-    limits.memory: "1200Mi"
-    limits.cpu: "2400m"
+    requests.memory: "400Mi"
+    requests.cpu: "250m"
+    limits.memory: "600Mi"
+    limits.cpu: "400m"
     pods: "9"