Add sticky session affinity to MCP IngressRoute

STREAMABLE transport holds session state in-memory per-pod. With HPA
scaling to 2+ replicas and round-robin routing, requests hit different
pods and fail with "Session not found". Pin each client to one pod via
a secure HttpOnly cookie.

servers/legion/k8s/neuron-technologies/prod/mcp-ingressroute.yaml

@@ -1,6 +1,8 @@
 # Traefik IngressRoute: neuron.neurontechnologies.ai → neuron-mcp service
 # Exposes the Neuron MCP server externally via Cloudflare tunnel.
 # MCP client config: url = https://neuron.neurontechnologies.ai/mcp
+# Sticky sessions required: STREAMABLE transport holds session state in-memory;
+# without affinity, multi-pod deploys fail with "Session not found".
 
 apiVersion: traefik.io/v1alpha1
 kind: IngressRoute
@@ -16,3 +18,8 @@ spec:
       services:
         - name: neuron-mcp
           port: 8080
+          sticky:
+            cookie:
+              name: neuron_mcp_affinity
+              secure: true
+              httpOnly: true