SSR should use AsyncLocalStorage for locale #7806
Description
During SSR, multiple requests with different locales could be running at the same time. This leads to PRs like #7804.
The locale is stored as a singleton in module scope in use-locale.ts, and setLocale() just changes that value.
Instead, it should use AsyncLocalStorage if that's available, and then withLocale should only be used once during request processing in qwik router.
We're already doing that to store the request event, for example.