fix: update pushState function to reflect the new url in the page store

[SunPodder]

fixes #11492

The pushState function was not updating the built-in page store properties ($pages.url and $pages.route) even though the actual URL in the browser was changed. This causes changes to not reflected on the UI if a component depends on any of those page store properties.

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[teemingc]

Thank for submitting this. Do you mind adding a test for it too?

[dummdidumm]

@Rich-Harris was it intended to be that way?
I'd like to clarify this first before we merge this - this might be a feature, not a bug.

[SunPodder]

Thank for submitting this. Do you mind adding a test for it too?

Also updated the replaceState function. Added tests for both.

[Rich-Harris]

$page.url and $page.route should not be updated when using pushState, because you're not actually changing the route