fix: ignore third-party monkeypatches in pushState/replaceState warning

[FrankFMY]

Summary

When third-party libraries like Sentry SDK monkeypatch history.pushState and history.replaceState, they insert additional stack frames. The dev-mode warning that checks if these methods are called from outside SvelteKit relies on stack trace inspection, but the extra frames from monkeypatching libraries cause false positives — the warning fires even for SvelteKit's own internal calls.

This PR filters out stack frames originating from node_modules before checking the call origin, so that monkeypatching libraries (Sentry, analytics tools, etc.) no longer trigger the false positive warning.

Before

Any library in node_modules that wraps history.pushState/replaceState (like @sentry/svelte) would cause the following false warning on every SvelteKit navigation:

Avoid using history.pushState(...) and history.replaceState(...) as these will conflict with SvelteKit's router.

After

Stack frames from node_modules are filtered out before the origin check, so SvelteKit correctly identifies its own internal calls regardless of how many third-party wrappers are in the call chain.

How it works

The stack trace for SvelteKit's internal pushState call with Sentry looks like:

warn (client.js)
history.pushState (client.js)   ← SvelteKit monkeypatch
pushState (sentry/instrument.js) ← Sentry monkeypatch (node_modules)
pushState (client.js)            ← SvelteKit internal call

After slice(2), the first frame is Sentry's — not client.js — triggering the false warning. By filtering node_modules frames, the first remaining frame is correctly identified as client.js.

Closes #12177

Test plan

• All unit tests pass (417 passed)
• All pushState-related integration tests pass
• All shallow routing tests pass (9 passed)
• Verified all four scenarios work correctly:
  • SvelteKit internal call without monkeypatch → no warning ✓
  • SvelteKit internal call with monkeypatch → no warning ✓
  • External call without monkeypatch → warning ✓
  • External call with monkeypatch → warning ✓

[changeset-bot]

🦋 Changeset detected

Latest commit: dfb77be

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-15267-svelte.vercel.app/

[dummdidumm]

Fix is good enough for me (I mean I originally proposed it), the possibility that something in node_modules initiated history.push is slim - but wanna get some other maintainer opinions here before merging