Fix more PR comments

Author: hhvrc

src/lib/tour/onboarding-state.ts

@@ -44,15 +44,10 @@ export function hasSeenWelcome(): boolean {
 
 export function markWelcomed(): void {
   try {
-    cookieStore
-      .set({
-        name: WELCOME_COOKIE_NAME,
-        value: 'true',
-        path: '/',
-        expires: WELCOME_COOKIE_EXPIRES.getTime(),
-        sameSite: 'lax',
-      })
-      .catch(() => {});
+    // Synchronous document.cookie write. The async cookieStore API would also work
+    // (Chrome 87+, Firefox 140+, Safari 18.4+), but for a one-shot write it buys
+    // nothing and drops older browsers, so the plain string write is preferred.
+    document.cookie = `${WELCOME_COOKIE_NAME}=true; path=/; expires=${WELCOME_COOKIE_EXPIRES.toUTCString()}; SameSite=Lax`;
   } catch {
     // ignore
   }

src/routes/+layout.server.ts

@@ -1,5 +1,5 @@
 import { SIDEBAR_COOKIE_NAME } from '$lib/components/ui/sidebar/constants';
-import { isWelcomeSunset, WELCOME_COOKIE_NAME } from '$lib/tour/onboarding-state';
+import { isOnboardingDisabled, isWelcomeSunset, WELCOME_COOKIE_NAME } from '$lib/tour/onboarding-state';
 import { isTruthy } from '$lib/utils/parse';
 import type { LayoutServerLoad } from './$types';
 
@@ -9,6 +9,12 @@ export const load: LayoutServerLoad = ({ cookies }) => {
   // state and we avoid a collapse-then-expand flash on hydration.
   const sidebarOpen = cookies.get(SIDEBAR_COOKIE_NAME) === 'true';
 
+  // When onboarding is disabled the client unmounts the screen immediately on
+  // hydration, so SSR-ing it just hurts LCP — skip it server-side too.
+  if (isOnboardingDisabled()) {
+    return { sidebarOpen, showWelcome: false };
+  }
+
   // Past the sunset date the welcome screen is retired — never SSR it, and clear
   // the cookie if a returning visitor still has it set.
   if (isWelcomeSunset()) {