chore: reorganize docs apps (#7228)

* reorganize docs apps

* add README

* fix directory

* add condition for old docs

www/apps/resources/app/commerce-modules/payment/payment-session/page.mdx

@@ -0,0 +1,35 @@
+export const metadata = {
+  title: `Payment Session`,
+}
+
+# {metadata.title}
+
+In this document, you’ll learn what a payment session is.
+
+## What's a Payment Session?
+
+A payment session, represented by the `PaymentSession` data model, is a payment amount to be authorized. It’s associated with a payment provider that handles authorizing it.
+
+A payment collection can have multiple payment sessions. For example, during checkout, when a customer chooses between paying with Stripe or PayPal, each of these payment options is a payment session associated with a payment provider (Stripe or PayPal).
+
+![Diagram showcasing how every payment session has a different payment provider](https://res.cloudinary.com/dza7lstvk/image/upload/v1711565056/Medusa%20Resources/payment-session-provider_guxzqt.jpg)
+
+---
+
+## data field
+
+Payment providers may need some additional data to process the payment later. The `PaymentSession` data model has a `data` field used to store that data.
+
+For example, for Stripe, you must pass Stripe’s customer ID when processing the payment. So, when you create a payment session, the Stripe payment provider creates the customer in Stripe and stores the ID in the `data` field.
+
+---
+
+## Payment Session Status
+
+The `status` field of a payment session indicates its current status. Its value can be:
+
+- `pending`: The payment session is awaiting authorization.
+- `requires_more`: The payment session requires an action before it’s authorized. For example, to enter a 3DS code.
+- `authorized`: The payment session is authorized.
+- `error`: An error occurred while authorizing the payment.
+- `canceled`: The authorization of the payment session has been canceled.