Add observability for webhooks filtered out or with failed filtering
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The following discussion from !224355 should be addressed:
> **thought**: one thing I noticed is that `FilterEvaluator.evaluate` rescues all `StandardError` and returns `false`, which means in case of an error the webhook is silently skipped and there is no `WebHookLog` entry for the user. While this error path is unlikely to be hit today (since filters can only be set via Rails console manually), it could become a real concern when the API/UI is introduced.
>
> Something to consider for the follow-up is also adding observability (e.g., `ErrorTracking.track_exception`, metrics).
issue