fix(loyalty): use Code 128 barcode for retail scanner compatibility

Switch wallet pass barcodes from QR to Code 128 format using the
card_number (digits only), so standard retail barcode scanners can
read loyalty cards. Apple Wallet keeps QR as fallback in barcodes
array. Also fix stale Vendor.loyalty_program relationship (now
company-based), add parent init calls in vendor JS components,
and update module docs to reflect Phase 2 completion.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/modules/loyalty/static/vendor/js/loyalty-card-detail.js

@@ -20,6 +20,12 @@ function vendorLoyaltyCardDetail() {
             if (window._loyaltyCardDetailInitialized) return;
             window._loyaltyCardDetailInitialized = true;
 
+            // IMPORTANT: Call parent init first to set vendorCode from URL
+            const parentInit = data().init;
+            if (parentInit) {
+                await parentInit.call(this);
+            }
+
             // Extract card ID from URL
             const pathParts = window.location.pathname.split('/');
             const cardsIndex = pathParts.indexOf('cards');