fix(effect): Add final metrics flush before layer teardown

Before this fix, when SentryEffectMetricsLayer was torn down, the release
effect only cleared previousCounterValues without flushing accumulated
metrics. Since the scoped fiber running the periodic reporter is
interrupted on scope finalization, any metrics accumulated since the
last 10-second flush were silently lost.

This fix adds a final flush before clearing the state, ensuring all
metrics are sent to Sentry before the layer is finalized.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: cursoragent

packages/effect/src/metrics.ts

@@ -126,6 +126,7 @@ export const SentryEffectMetricsLayer: Layer.Layer<never, never, never> = scoped
 
     yield* Effect.acquireRelease(Effect.void, () =>
       Effect.sync(() => {
+        flushMetricsToSentry(previousCounterValues);
         previousCounterValues.clear();
       }),
     );