On the beta cluster, we currently suppress event sending whenever a user forces enrollment via the override. This mirrors production, where suppression makes sense: we don't want test events polluting the real event stream.

However, beta cluster has its own event stream (https://stream.wikimedia.beta.wmcloud.org/v2/ui/#/) so pollution isn't a risk. The override is the only practical way to test scenarios that enroll such small proportions of users, and using it means no events are sent at all. Yet it's exactly when we want to observe them. Devtools x browser interactions make it unreliable to confirm event sending by clicking through the UI and looking for responses in the console, which is what surfaced this suppression as the real blocker.

The goal here is to lift the override suppression on the beta cluster: allow events to send to the beta stream even when the enrollment override is in use. Production behaviour stays unchanged.

Acceptance Criteria

• With enrollment override active on beta, instrumented interactions produce events to the beta stream
• Events are observable via the beta stream UI
• Production behaviour is unchanged: override still suppresses sending on prod
• Events from overridden experiments have experiment.coordinator set to "forced"
• Events with experiment.coordinator=forced are excluded from analysis everywhere
• The console log lines are kept
• Per-event contextual attributes are logged with the console log lines
• Documentation has been updated according to the work done here