Add freemium variant C: archetype persistence, dashboard banner, lesson gate

- User.archetype/utmSource/utmMedium/utmCampaign fields + migration
- register flow reads ?archetype/?utm_* and saves them on the User row
- dashboard ArchetypeBanner: per-archetype 'твой путь' block
- lesson gate after wow-moment lesson (WOW_MOMENT_LESSON_ID=obs-start-l2-006) → tripwire + full-course offer

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/(student)/dashboard/page.tsx

@@ -3,6 +3,7 @@ import { auth } from "@/lib/auth";
 import { redirect } from "next/navigation";
 import { prisma } from "@/lib/prisma";
 import Link from "next/link";
+import { ArchetypeBanner } from "@/components/student/archetype-banner";
 
 // Продаваемая линейка курсов → лендинг продукта. Курсы из этого списка,
 // которых нет у студента, показываются на дашборде заблюренными карточками
@@ -19,6 +20,11 @@ export default async function StudentDashboard() {
   const session = await auth.api.getSession({ headers: await headers() });
   if (!session) redirect("/login");
 
+  const dbUser = await prisma.user.findUnique({
+    where: { id: session.user.id },
+    select: { archetype: true },
+  });
+
   const enrollments = await prisma.courseEnrollment.findMany({
     where: { userId: session.user.id },
     include: {
@@ -79,6 +85,8 @@ export default async function StudentDashboard() {
         {active.length} активных курсов
       </p>
 
+      {dbUser?.archetype && <ArchetypeBanner archetype={dbUser.archetype} />}
+
       {active.length === 0 ? (
         <div className="card-aubade p-12 text-center">
           <p className="text-4xl mb-3">📚</p>