fix(astro): resolve non-ASCII target paths in Astro.rewrite
When rewriting to a path containing non-ASCII characters (e.g.,
`/redirected/héllo`), the `findRouteToRewrite` function compared
encoded `distURL` hrefs against decoded pathnames, causing a mismatch
and a 404 response.
The fix compares `url.href` against the encoded `pathname` instead of
`decodedPathname`, since URL hrefs are always percent-encoded.
Closes #14464