feat(toolrate): rebrand to toolr + logo links home

- visible brand text changed to toolr (sidebar, mobile header, topbar
  fallback, login, 404, home heading, index.html title/og/twitter meta)
- brand logo now links to / in sidebar, mobile header, login, 404
- internal identifiers unchanged: package name, localStorage key

artifacts/toolrate/src/pages/login.tsx

@@ -46,10 +46,10 @@ export default function Login() {
       </div>
       <div className="w-full max-w-sm space-y-6">
         <div className="flex flex-col items-center gap-2 text-center">
-          <div className="flex items-center gap-2 text-primary font-bold text-2xl">
+          <Link href="/" className="flex items-center gap-2 text-primary font-bold text-2xl">
             <Wrench className="w-7 h-7" />
-            <span>ToolRate</span>
-          </div>
+            <span>toolr</span>
+          </Link>
           <p className="text-muted-foreground text-sm">Sign in to your account</p>
         </div>