feat(kube): restrict MC RCON access to kilobase namespace

[h0lybyte]

Summary

• Adds a NetworkPolicy to the MC Kubernetes manifests that restricts RCON (port 25575) access to only the kilobase and mc namespaces
• Game (25565/TCP), Bedrock (19132/UDP), and Resource Pack (8080/TCP) ports remain unrestricted
• RCON is accessible internally at mc-service.mc.svc.cluster.local:25575

Test plan

• Verify RCON connection succeeds from a pod in the kilobase namespace
• Verify RCON connection is denied from pods in other namespaces
• Verify game/bedrock/resource-pack traffic is unaffected

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None