- Fixed `SentryMetrics` silently dropping `MetricsFrame`s from `stop_ttfb_metrics` and `stop_processing_metrics`. `SentryMetrics` called the base `FrameProcessorMetrics` implementation but discarded its return value, so `FrameProcessor` never pushed the `MetricsFrame` downstream. This prevented observers (e.g. `UserBotLatencyObserver`, `MetricsLogObserver`) from seeing TTFB and processing metrics for any service using `metrics=SentryMetrics()`. The metrics were still calculated and Sentry transactions still completed — only the downstream frame push was affected.