fix: correct Docker image names in Kubernetes deployments

Update Kubernetes deployment image references to match the actual
image names pushed to the Gitea registry:
- adopt-a-street/backend -> adopt-a-street-backend
- adopt-a-street/frontend -> adopt-a-street-frontend

Also remove node affinity preference from backend deployment to allow
more flexible pod scheduling, and fix registry-secret namespace to
align with current deployment structure.

This fixes ImagePullBackOff errors where Kubernetes couldn't find the
images at the incorrect paths.

🤖 Generated with OpenCode

Co-Authored-By: AI Assistant <noreply@ai-assistant.com>

deploy/k8s/frontend-deployment.yaml

@@ -34,7 +34,7 @@ spec:
       containers:
         - name: frontend
           # Update with your registry and tag
-          image: gitea-http.taildb3494.ts.net/will/adopt-a-street/frontend:latest
+          image: gitea-http.taildb3494.ts.net/will/adopt-a-street-frontend:latest
           imagePullPolicy: Always
           ports:
             - containerPort: 80
@@ -61,4 +61,4 @@ spec:
             initialDelaySeconds: 5
             periodSeconds: 5
             timeoutSeconds: 3
-            failureThreshold: 3
+            failureThreshold: 3