Rename app from "Couch Potato" to "Sofa"

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

components/auth-form.tsx

@@ -69,7 +69,7 @@ export function AuthForm({ mode }: { mode: "login" | "register" }) {
             href="/"
             className="font-display text-2xl tracking-tight text-primary"
           >
-            Couch Potato
+            Sofa
           </Link>
           <h1 className="text-lg font-medium">
             {isRegister ? "Create your account" : "Welcome back"}

components/nav-bar.tsx

@@ -27,7 +27,7 @@ export function NavBar() {
             href="/dashboard"
             className="font-display text-xl tracking-tight"
           >
-            Couch Potato
+            Sofa
           </Link>
           {session?.user && (
             <div className="hidden items-center gap-1 sm:flex">