Remove unused links from navigation

Drop /start, /faq (q&a), /library, /ai and /changelog from site
navigation

src/components/Nav.astro

@@ -3,19 +3,14 @@ const currentPath = Astro.url.pathname;
 
 const links = [
     { href: "/", label: "home" },
-    { href: "/start", label: "start" },
-    { href: "/faq", label: "q&a" },
     { href: "/about", label: "about" },
     { href: "/projects", label: "projects" },
     { href: "/now", label: "now" },
     { href: "/uses", label: "uses" },
     { href: "/blog", label: "blog" },
     { href: "/coffee", label: "coffee" },
-    { href: "/library", label: "library" },
     { href: "/links", label: "links" },
     { href: "/guestbook", label: "guestbook" },
-    { href: "/ai", label: "ai" },
-    { href: "/changelog", label: "changelog" },
 ];
 
 function isActive(href: string, current: string): boolean {