feat(payment): connect payment service flow

src/stores/payment/index.ts

@@ -0,0 +1,9 @@
+/**
+ * @file Payment store barrel.
+ */
+
+export * from "./payment-context";
+export * from "./payment-events";
+export * from "./payment-machine";
+export * from "./payment-machine.actors";
+export * from "./payment-state";