test(nextjs): Skip Turbopack-only server-component streaming tests on webpack

The new webpack variant runs the whole nextjs-16-streaming suite under webpack,
including two server-component tests that assert Turbopack-internal span names
(`build component tree`, `resolve page components`, ...) that webpack never
emits. Gate them on the SDK's `turbopack` span attribute (TEST_ENV=production is
shared by both prod variants, so env alone cannot distinguish them).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: chargome

dev-packages/e2e-tests/test-applications/nextjs-16-streaming/tests/server-components.test.ts

@@ -2,6 +2,13 @@ import { expect, test } from '@playwright/test';
 import { waitForStreamedSpan, waitForStreamedSpans, getSpanOp } from '@sentry-internal/test-utils';
 import { isDevMode } from './isDevMode';
 
+// The SDK sets a `turbopack` span attribute (from build metadata) on Turbopack builds. Since
+// TEST_ENV=production is shared by the turbopack and webpack prod variants, this is the only reliable
+// way to tell them apart at runtime.
+function isTurbopackBuild(spans: Array<{ attributes: Record<string, { value?: unknown }> }>): boolean {
+  return spans.some(span => span.attributes['turbopack']?.value === true);
+}
+
 test('Sends a streamed span for a request to app router with URL', async ({ page }) => {
   test.skip(isDevMode, 'Turbopack intermittently returns 404 for nested dynamic routes in dev mode');
 
@@ -31,6 +38,11 @@ test('Will create streamed spans for every server component and metadata generat
   const spans = await spansPromise;
   const spanNames = spans.map(span => span.name);
 
+  // These are Next.js-internal server-component spans that only Turbopack emits - webpack produces a
+  // different span set. TEST_ENV=production is shared by both prod variants, so gate on the independent
+  // `turbopack` attribute (set by the SDK from build metadata) instead of the env.
+  test.skip(!isTurbopackBuild(spans), 'Server component spans are only emitted by Turbopack builds');
+
   expect(spanNames).toContainEqual('render route (app) /nested-layout');
   expect(spanNames).toContainEqual('build component tree');
   expect(spanNames).toContainEqual('resolve root layout server component');
@@ -55,6 +67,9 @@ test('Will create streamed spans for every server component and metadata generat
   const spans = await spansPromise;
   const spanNames = spans.map(span => span.name);
 
+  // See note above - these server-component spans are only emitted by Turbopack builds.
+  test.skip(!isTurbopackBuild(spans), 'Server component spans are only emitted by Turbopack builds');
+
   expect(spanNames).toContainEqual('resolve page components');
   expect(spanNames).toContainEqual('render route (app) /nested-layout/[dynamic]');
   expect(spanNames).toContainEqual('build component tree');