System traffic no longer counts as application message metrics (CritterWatch GH-907)

[jeremydmiller]

Fixes the Wolverine half of CritterWatch #907: an idle Wolverine app with CritterWatch applied reported ~150 messages/minute of nothing but its own machinery — agent commands on the control queues, acks, and CritterWatch's monitoring messages, the last of which fed back on itself (accumulator exports are published to CritterWatch as messages that were themselves counted).

The three gaps

1. Meter counters were unconditional. wolverine-messages-sent incremented for every send regardless of what the traffic was (the TelemetryEnabled flag gated spans, never metrics). Sending agents, local queues, and listening pipelines now resolve their tracker via MessageTrackingFor(endpoint) — a System-role endpoint or one with TelemetryEnabled = false gets a new metrics-silent SystemTrafficMessageTracker that keeps debug logging, tracked-session bookkeeping, and wire taps, but records nothing.
2. The executor factory excluded only IAgentCommand, and only in the CritterWatch modes. It now excludes the full system-message surface via the existing IsSystemMessageType() predicate (IInternalMessage, IAgentCommand, INotToBeRouted — which covers ICritterWatchMessage and acknowledgements — and opted-out assemblies), in every metrics mode, and consults the endpoint role too.
3. UseTcpForControlEndpoint never stamped the System role on the endpoint it promoted, unlike the database/shared-memory control endpoints that are born with it. The NodeControlEndpoint setter stamps it now.

Design constraints honored (from the issue)

• No per-envelope branching: every decision is resolved once at construction (per endpoint agent, per executor) — the sendWithTracing/sendWithOutTracing pattern.
• EndpointRole, not string matching, is the classification the system relies on; the old IsSystemEndpoint string match stays only as defense in depth on the accumulator paths.

Behavior change to be aware of

Endpoint.TelemetryEnabled = false now silences metrics as well as traces for that endpoint, and system message types no longer appear in any message-level instrument in any mode. The metrics docs gained a callout.

Testing

• New system_traffic_metrics_silencing suite in CoreTests (9 tests): tracker selection per role/flag/message type, control-endpoint promotion, and MeterListener-verified silence vs. counting.
• Full CoreTests: 2176 passed. MetricsTests: 25 passed — including the pump tests that prove application traffic is still counted in CritterWatch/Hybrid modes.

Companion change

Wolverine.CritterWatch will mark its own outbound/inbound endpoints System-role in a CritterWatch-repo PR (InternalsVisibleTo already covers it); end-to-end idle-app verification lands there per the issue.

🤖 Generated with Claude Code

https://claude.ai/code/session_013eR4GL278688VhyhrGcttJ