perf(routing): resolve entry route and intro rendering directly in SSR

src/app/[lang]/page.tsx

@@ -7,6 +7,10 @@ import {
   isAuthenticatedToken,
   MARRIAGE_ENTRY_PATH_COOKIE,
 } from "@/lib/entry-route-cache";
+import {
+  getSubmitPath,
+  hasCompletedMarriageProfileBasics,
+} from "@/lib/get-submit-path";
 import { localizePath } from "@/translations/config";
 
 export const dynamic = "force-dynamic";
@@ -30,10 +34,41 @@ export default async function LocaleEntryPage({
     redirect(localizePath(cachedEntryPath, lang));
   }
 
+  // 1. If not authenticated, render <Intro /> instantly on the server (0ms client delay)
+  if (!hasToken) {
+    return <Intro />;
+  }
+
+  // 2. If authenticated without cached route, resolve target route directly on the server
+  let targetPath: string | null = null;
+  const apiBaseUrl = process.env.NEXT_PUBLIC_API_BASE_URL;
+  if (apiBaseUrl) {
+    try {
+      const res = await fetch(`${apiBaseUrl}/api/marriage/profile/main/`, {
+        headers: {
+          Authorization: `Token ${token}`,
+          Accept: "application/json",
+        },
+        cache: "no-store",
+      });
+      if (res.ok) {
+        const profile = await res.json();
+        targetPath = hasCompletedMarriageProfileBasics(profile)
+          ? getSubmitPath(profile)
+          : "/intro";
+      }
+    } catch {
+      // Graceful fallback to client-side resolver if server fetch fails
+    }
+  }
+
+  if (targetPath) {
+    redirect(localizePath(targetPath, lang));
+  }
+
   return (
     <>
-      {!hasToken ? <Intro /> : null}
-      <EntryRouteResolver anonymousEntryVisible={!hasToken} />
+      <EntryRouteResolver anonymousEntryVisible={false} />
     </>
   );
 }