feat(browser): Detect redirects when emitting navigation spans

[mydea]

Closes #15286

This PR adds a new option to browserTracingIntegration, detectRedirects, which is enabled by default. If this is enabled, the integration will try to detect if a navigation is actually a redirect based on a simple heuristic, and in this case, will not end the ongoing pageload/navigation, but instead let it run and create a navigation.redirect zero-duration span instead.

An example trace for this would be: https://sentry-sdks.sentry.io/explore/discover/trace/95280de69dc844448d39de7458eab527/?dataset=transactions&eventId=8a1150fd1dc846e4ac8420ccf03ad0ee&field=title&field=project&field=user.display&field=timestamp&name=All%20Errors&project=4504956726345728&query=&queryDataset=transaction-like&sort=-timestamp&source=discover&statsPeriod=5m&timestamp=1747646096&yAxis=count%28%29

Where the respective index route that triggered this has this code:

setTimeout(() => {
  window.history.pushState({}, "", "/test-sub-page");
  fetch('https://example.com')
}, 100);

The used heuristic is:

• If the ongoing pageload/navigation was started less than 300ms ago...
• ... and no click has happened in this time...
• ... then we consider the navigation a redirect

this limit was chosen somewhat arbitrarily, open for other suggestions too.

While this logic will not be 100% bullet proof, it should be reliable enough and likely better than what we have today. Users can opt-out of this logic via browserTracingIntegration({ detectRedirects: false }), if needed.

[github-actions]

size-limit report 📦

Path	Size	% Change	Change
@sentry/browser	23.95 kB	-	-
@sentry/browser - with treeshaking flags	23.72 kB	-	-
@sentry/browser (incl. Tracing)	38.47 kB	+0.52%	+197 B 🔺
@sentry/browser (incl. Tracing, Replay)	76.59 kB	+0.27%	+199 B 🔺
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	69.67 kB	+0.25%	+171 B 🔺
@sentry/browser (incl. Tracing, Replay with Canvas)	81.37 kB	+0.25%	+199 B 🔺
@sentry/browser (incl. Tracing, Replay, Feedback)	93.47 kB	+0.23%	+208 B 🔺
@sentry/browser (incl. Feedback)	40.72 kB	-	-
@sentry/browser (incl. sendFeedback)	28.68 kB	-	-
@sentry/browser (incl. FeedbackAsync)	33.57 kB	-	-
@sentry/react	25.73 kB	-	-
@sentry/react (incl. Tracing)	40.46 kB	+0.51%	+204 B 🔺
@sentry/vue	28.35 kB	-	-
@sentry/vue (incl. Tracing)	40.31 kB	+0.54%	+215 B 🔺
@sentry/svelte	23.98 kB	-	-
CDN Bundle	25.25 kB	-	-
CDN Bundle (incl. Tracing)	38.56 kB	+0.45%	+172 B 🔺
CDN Bundle (incl. Tracing, Replay)	74.45 kB	+0.26%	+193 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback)	79.86 kB	+0.24%	+186 B 🔺
CDN Bundle - uncompressed	73.67 kB	-	-
CDN Bundle (incl. Tracing) - uncompressed	114.12 kB	+0.38%	+427 B 🔺
CDN Bundle (incl. Tracing, Replay) - uncompressed	228.09 kB	+0.19%	+427 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	240.92 kB	+0.18%	+427 B 🔺
⛔️ @sentry/nextjs (client) (max: 42 kB)	42.12 kB	+0.51%	+212 B 🔺
@sentry/sveltekit (client)	38.96 kB	+0.54%	+207 B 🔺
@sentry/node	149.51 kB	-	-
@sentry/node - without tracing	98.12 kB	-	-
@sentry/aws-serverless	123.46 kB	-	-

View base workflow run

[codecov]

❌ Unsupported file format

Upload processing failed due to unsupported file format. Please review the parser error message:

Error parsing JUnit XML in /home/runner/work/sentry-javascript/sentry-javascript/packages/solidstart/vitest.junit.xml at 18:17

Caused by:
    RuntimeError: Error parsing XML
    
    Caused by:
        0: ill-formed document: expected `</testsuites>`, but `</testsuite>` was found
        1: expected `</testsuites>`, but `</testsuite>` was found

For more help, visit our troubleshooting guide.

[s1gr1d]

Suggested change

	DEBUG_BUILD && logger.warn('[Tracing] Detected redirect, navigation span will not be the root span.');
	DEBUG_BUILD && logger.warn('[Tracing] Detected redirect, navigation span will not be the root span, but a child span.');