feat: convert to nextjs

.env.example

@@ -1,3 +1,13 @@
-DATABASE_URL="postgresql://postgres:postgres@localhost:5433/persona?schema=public&connect_timeout=300"
-PURCHASE_REFLECTION_THRESHOLD=50
 ANTHROPIC_API_KEY=
+NEXT_PUBLIC_CONTACT_EMAIL=
+POSTGRES_DATABASE=
+POSTGRES_HOST=
+POSTGRES_PASSWORD=
+POSTGRES_PRISMA_URL=
+POSTGRES_URL=
+POSTGRES_URL_NON_POOLING=
+POSTGRES_URL_NO_SSL=
+POSTGRES_USER=
+PURCHASE_REFLECTION_THRESHOLD=
+NUMBER_OF_WEEKS=
+RATE_LIMIT=