test: wait for cancelled popstate navigation

[svelte-triage-bot]

Fixes a flaky navigation lifecycle test observed in PR #16900 and CI run 32992201226.

When a popstate navigation is cancelled, SvelteKit performs a compensating history traversal. page.goBack() can resolve before that traversal and the resulting reactive DOM update have settled, causing the test to read the initial state. Use Playwright web-first assertions for both the rendered navigation state and restored URL.

Verification:

• five separate focused runs passed
• 200 dev-mode repeats with four workers passed
• 100 build-mode repeats with four workers passed
• 18 nearby navigation lifecycle tests passed
• full cross-platform client spec passed with one worker (97 tests)

[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from d9ec623:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/d9ec6235fdf843adf3c03fc712b0b99be7d65ad7

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16945

Note

This PR is from a fork. A maintainer must approve approve each commit before it can be built and installed.

[changeset-bot]

⚠️ No Changeset found

Latest commit: d9ec623

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