fix: Fixed paddle subs

admin/internal/paddle/client.go

@@ -25,6 +25,10 @@ type Client interface {
 	// immediately by Paddle. This is the one outbound mutation, used when a
 	// customer changes their server count or features on an existing plan.
 	UpdateSubscriptionItems(ctx context.Context, paddleSubscriptionID string, items []LineItem) error
+	// UpdateSubscriptionCustomData replaces a subscription's custom_data. Used
+	// when a self-hosted placeholder is claimed: the checkout attached the
+	// placeholder id, and every later webhook must name the real install UUID.
+	UpdateSubscriptionCustomData(ctx context.Context, paddleSubscriptionID string, data map[string]string) error
 	// PortalSession returns a customer-portal URL for managing billing.
 	PortalSession(ctx context.Context, paddleCustomerID string) (string, error)
 	// Env is "sandbox" or "production", the same value catalogue price lookups

admin/internal/paddle/http.go

@@ -99,6 +99,17 @@ func (c *httpClient) UpdateSubscriptionItems(ctx context.Context, subID string,
 	}, nil)
 }
 
+// UpdateSubscriptionCustomData patches custom_data only. Paddle replaces the
+// whole object, so callers pass every key they want to keep.
+func (c *httpClient) UpdateSubscriptionCustomData(ctx context.Context, subID string, data map[string]string) error {
+	if subID == "" {
+		return fmt.Errorf("paddle: empty subscription id")
+	}
+	return c.do(ctx, http.MethodPatch, "/subscriptions/"+subID, struct {
+		CustomData map[string]string `json:"custom_data"`
+	}{CustomData: data}, nil)
+}
+
 func (c *httpClient) PortalSession(ctx context.Context, customerID string) (string, error) {
 	if customerID == "" {
 		return "", fmt.Errorf("paddle: empty customer id")