Fix unlocalized logo link - use localizeHref for homepage

The logo link was hardcoded to '/' which meant Spanish users on /es/ pages
would be taken back to the English homepage when clicking the logo.

Now uses localizeHref('/') to properly localize the link, so Spanish users
stay in /es/ when clicking the logo.

Fixes part of the issues described in #448

Author: Anthony Bailey

src/routes/header.svelte

@@ -28,7 +28,7 @@
 	<div class="logo-container">
 		<div class="compensate-min-space-between" />
 		<div class="compensate-offset" />
-		<a href="/" class="logo">
+		<a href={localizeHref('/')} class="logo">
 			<Logo animate={logo_animate} {inverted} />
 		</a>
 		<div class="min-space-between" />