Docker mode still probes kubernetes-default during deployment discovery

[timflannagan]

In docker mode, deployment discovery still attempts Kubernetes provider discovery and logs kubeconfig warnings:

# 03f28fb3a8ee   localhost:5001/agentregistry-dev/agentregistry/server:v0.3.2-12-g10526cb   "/bin/sh -c 'if [ -f…"   17 minutes ago   Up 17 minutes             0.0.0.0:12121->8080/tcp, [::]:12121->8080/tcp   agentregistry-server
$ docker logs 03f28fb3a8ee -f
...
{"time":"2026-03-19T18:19:10.21407792Z","level":"INFO","msg":"Warning: failed to list kubernetes agents for discovery: failed to create kubernetes client: failed to get kubernetes config: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable"}
{"time":"2026-03-19T18:19:10.214162837Z","level":"INFO","msg":"Warning: failed to list kubernetes MCP servers for discovery: failed to create kubernetes client: failed to get kubernetes config: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable"}
{"time":"2026-03-19T18:19:10.214225504Z","level":"INFO","msg":"Warning: failed to list kubernetes remote MCP servers for discovery: failed to create kubernetes client: failed to get kubernetes config: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable"}

When streaming those logs, list the deployments and notice the new warning log messages:

$ arctl deployments list