chore(k8s): drop CPU and memory requests

Requests are set to an explicit 0 instead of being removed, because
Kubernetes defaults a missing request to the limit, which would reserve
even more. Limits stay as an upper bound.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

deploy/k8s/backend/deployment.yaml

@@ -48,8 +48,8 @@ spec:
             periodSeconds: 10
           resources:
             requests:
-              cpu: 100m
+              cpu: "0"
-              memory: 128Mi
+              memory: "0"
             limits:
               cpu: 500m
               memory: 512Mi

deploy/k8s/frontend/deployment.yaml

@@ -30,8 +30,8 @@ spec:
             periodSeconds: 10
           resources:
             requests:
-              cpu: 100m
+              cpu: "0"
-              memory: 128Mi
+              memory: "0"
             limits:
               cpu: 500m
               memory: 512Mi

deploy/k8s/postgres/statefulset.yaml

@@ -42,8 +42,8 @@ spec:
             periodSeconds: 10
           resources:
             requests:
-              cpu: 250m
+              cpu: "0"
-              memory: 256Mi
+              memory: "0"
             limits:
               cpu: "1"
               memory: 1Gi