fix: skip navigation if only url hash change

[bluwy]

Fixes #3105
Fixes #2667

If only the URL hash change when navigating via anchor tags, e.g. <a href="#foo">, skip router navigation and let the default browser behaviour to kick in.

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Latest commit: ed91ca8

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[bluwy]

Changed this to page.click and page.goBack since the clicknav and back utils rely on sveltekit:navigation-end to resolve, which these hash-only anchor tags would skip, resulting in timeout.

Using playwright's builtin functions to avoid it.

[bluwy]

In no-js, the default page focus after Tab is the document body, which fails this test. I'm not entirely clear why it works in js, but I'm skipping this for now.