Scale staging to 2 replicas (#239)

Stateless HTTP mode + Redis-backed state means replicas are safe
to run behind the L7 load balancer with no session affinity needed.

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: RafaelPo

everyrow-mcp/deploy/chart/values.staging.yaml

@@ -6,6 +6,8 @@
 # EVERYROW_API_URL is intentionally not overridden — there is no staging API.
 # The MCP server is a frontend to the production EveryRow API in both environments.
 
+replicaCount: 2
+
 env:
   MCP_SERVER_URL: "https://mcp-staging.everyrow.io"
   REDIS_DB: "14"