feat: deploy to Frostmoln production (#417)

Part of the dancefinder.unbound.se cutover to Frostmoln Production (infra: unboundsoftware/infra#1896, already applied).

- Replaces the AWS `deploy-prod` job (failing since CI left AWS) with `deploy-prod-frostmoln` (`deploy prod-frostmoln -n dancefinder`), as schemas did.
- Restricted securityContext (runAsNonRoot, drop ALL, seccomp RuntimeDefault) and `imagePullSecrets: oci-registry` (Platform registry).
- Listens on 8080 (`PORT`) as uid 65534. MAPS_API_KEY comes from the namespace's SecretStore (Frostmoln Secret `dancefinder`).

Merging deploys to Frostmoln only; DNS still points at AWS until the cutover.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

https://claude.ai/code/session_01H6eVuR4Yt3m7TbDTDwyZJi
Reviewed-on: https://gitea.unbound.se/dancefinder/geo-service/pulls/417

k8s/deploy.yaml

@@ -21,6 +21,13 @@ spec:
       labels:
         app.kubernetes.io/name: geo-service
     spec:
+      imagePullSecrets:
+        - name: oci-registry
+      securityContext:
+        runAsNonRoot: true
+        runAsUser: 65534
+        seccompProfile:
+          type: RuntimeDefault
       affinity:
         podAntiAffinity:
           preferredDuringSchedulingIgnoredDuringExecution:
@@ -35,6 +42,10 @@ spec:
                 topologyKey: kubernetes.io/hostname
       containers:
         - name: geo-service
+          securityContext:
+            allowPrivilegeEscalation: false
+            capabilities:
+              drop: ["ALL"]
           resources:
             limits:
               memory: "100Mi"
@@ -43,8 +54,11 @@ spec:
           imagePullPolicy: Always
           image: ${IMAGE}
           ports:
-            - containerPort: 80
+            - containerPort: 8080
               name: http
+          env:
+            - name: PORT
+              value: "8080"
           envFrom:
             - secretRef:
                 name: geo-service
@@ -59,7 +73,7 @@ spec:
     - port: 80
       name: http
       protocol: TCP
-      targetPort: 80
+      targetPort: 8080
   selector:
     app.kubernetes.io/name: geo-service
   type: ClusterIP