feat: add SwitchOffer component to promote switching from competitors for enhanced user engagement

apps/api/src/controllers/Users.ts

@@ -230,6 +230,14 @@ export class Users {
       client_reference_id: project.id, // Store project ID for webhook
       line_items: lineItems,
       ...(checkoutCurrency && {currency: checkoutCurrency}),
+      custom_fields: [
+        {
+          key: 'promo_code',
+          label: {type: 'custom', custom: 'Promo code'},
+          type: 'text',
+          optional: true,
+        },
+      ],
       subscription_data: {
         billing_cycle_anchor: billingCycleAnchor,
       },

apps/api/src/controllers/Webhooks.ts

@@ -530,10 +530,24 @@ export class Webhooks {
             },
           });
 
+          // Base onboarding credit: refund the 1-unit card-verification charge
+          let creditBalance = -100;
+
+          // Switching-offer promo: 2 extra units of credit if the customer typed SWITCH
+          // into the Promo code custom field on Stripe Checkout.
+          const promoField = session.custom_fields?.find((f) => f.key === 'promo_code');
+          const promoCode = promoField?.text?.value?.trim().toUpperCase();
+          if (promoCode === 'SWITCH') {
+            creditBalance -= 200;
+            signale.success(`[WEBHOOK] SWITCH promo applied for project ${projectId}`);
+          } else if (promoCode) {
+            signale.info(`[WEBHOOK] Unknown promo code "${promoCode}" entered for project ${projectId}`);
+          }
+
           // Update Stripe customer name to match project name and add credit for onboarding fee
           await stripe.customers.update(customerId, {
             name: updatedProject.name,
-            balance: -100,
+            balance: creditBalance,
           });
 
           signale.success(`[WEBHOOK] Checkout completed for project ${projectId}`);