Catalog: 20s cache so ladder pages stop waiting on five live quotes

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

server.js

@@ -88,6 +88,7 @@ async function uplineSlides(email, depth = 3) {
 // positions 2 and 3 become theirs at 2 and 5 qualifying buyers (the same
 // thresholds that open payout levels 2 and 3). Until then, or while an unlocked
 // slot is empty, the slot shows an upline's banner, then a house ad.
+const catalogCache = { at: 0, products: null };
 const wallUnlockedFor = bc => (bc >= 5 ? 3 : bc >= 2 ? 2 : 1);
 // every on-chain member id this session controls: the main wallet plus linked
 // positions (Qualified Start). Credits pool across them on the dashboard.
@@ -545,7 +546,13 @@ const server = http.createServer(async (req, res) => {
       return json(res, 200, { url: 'https://www.moonpay.com/buy/pol', signed: false, pol });
     }
     if (p === '/api/catalog' && req.method === 'GET') {
-      return json(res, 200, { products: await chain.catalog() });
+      // five live quotes per call: serve a 20-second cache so pages that load the
+      // ladder (join, home, buy) are not waiting on the RPC every time
+      if (!catalogCache.at || Date.now() - catalogCache.at > 20000) {
+        try { catalogCache.products = await chain.catalog(); catalogCache.at = Date.now(); }
+        catch (e) { if (!catalogCache.products) throw e; }
+      }
+      return json(res, 200, { products: catalogCache.products });
     }
     if (p === '/api/feed' && req.method === 'GET') {
       return json(res, 200, { events: await attachNames(chain.recentEvents(Number(u.searchParams.get('n')) || 100)) });