fix: prevent incorrect searchParams being applied on certain navs (#76914)
When the router returns an aliased prefetch for URLs to the same path
but with different search params, there's the possibility that we
trigger an MPA-style navigation if the path doesn't contain a valid
flight payload (eg: a route handler, a `pages` router page, or an
external URL). The logic to bail out of the alias handling was happening
_after_ this, which meant the incorrect searchParams would be applied to
the final URL.
This ensures that if we bail out of applying the alias (eg because it's
not a valid RSC payload, or the aliased entry has no reusable loading
segment), then we re-run the navigation with a non-aliased entry.
Fixes #75318
Closes NDX-804