bug(operator): MCPRegistry deprecation warning logs on a timer even when no MCPRegistry CRs exist

[RaviTharuma]

Bug description

The operator logs this on a timer even when zero MCPRegistry objects exist in the cluster:

Warning: MCPRegistry is deprecated and will be removed in a future release; install the ToolHive registry server via the toolhive-registry-server Helm chart (https://github.com/stacklok/toolhive-registry-server) instead logger=controller-runtime/cache

On v0.43.0 we see it about every 6 minutes from deploy/toolhive-operator, mixed into the VirtualMCPServer reconcile logs.

It is a cache/informer warning, not an event on a CR, so it cannot be silenced by not installing the CRD users already do not use.

Steps to reproduce

1. Install ToolHive operator v0.43.0. Do not create any MCPRegistry.
2. kubectl logs deploy/toolhive-operator -n <ns> | grep MCPRegistry

Expected behavior

• If no MCPRegistry CRs exist, do not warn.
• If the CRD is still registered, warn once at startup (or when the first CR appears), not on every cache resync.

Actual behavior

Periodic warning forever on clusters that never used MCPRegistry. Looks like an error during incident response; it is not.

Environment (if relevant)

• OS/version: Talos Linux, Kubernetes
• ToolHive version: operator v0.43.0

Additional context

We do not need the old registry CRD. If the operator still watches it for conversion, a single startup log plus the Helm-chart link is enough.

No credentials or private hostnames in this report.

[reyortiz3]

Thanks for the clear report, @RaviTharuma, and for pinpointing that this is a cache/informer-level warning rather than something tied to a CR event. We have read this and it is noted.

This is a good candidate for a community contribution if you or anyone else would like to pick it up — likely a matter of moving the warning to controller startup (or guarding it with a sync.Once) instead of logging it on every cache resync. I have labelled it good first issue. Open a draft PR or comment here and we will help with direction.

Thanks again for taking the time to file it.