docs: document how prices are stored in Medusa (#13362)

www/apps/resources/app/commerce-modules/pricing/concepts/page.mdx

@@ -6,11 +6,21 @@ export const metadata = {
 
 In this document, you’ll learn about the main concepts in the Pricing Module.
 
+## Price Data Model
+
+The [Price](/references/pricing/models/Price) data model represents a specific price for a resource. For example, the price of a product variant in the USD currency.
+
+The `Price` data model has an `amount` property that represents the monetary value of the price. It's stored as an integer in base units. For example, `$20.00` is stored as `20`.
+
+The `Price` data model belongs to other data models like `PriceSet` and `PriceList` to provide a variety of pricing features, as explained below.
+
+---
+
 ## Price Set
 
-A [PriceSet](/references/pricing/models/PriceSet) represents a collection of prices that are linked to a resource (for example, a product or a shipping option).
+A [PriceSet](/references/pricing/models/PriceSet) represents a collection of prices that are linked to a resource (for example, a product variant or a shipping option).
 
-Each of these prices are represented by the [Price data module](/references/pricing/models/Price).
+Each of these prices is represented by the [Price data model](/references/pricing/models/Price).
 
 ![A diagram showcasing the relation between the price set and price](https://res.cloudinary.com/dza7lstvk/image/upload/v1709648650/Medusa%20Resources/price-set-money-amount_xeees0.jpg)
 

www/apps/resources/app/commerce-modules/pricing/price-calculation/page.mdx

@@ -166,27 +166,27 @@ const priceSet = await pricingModuleService.createPriceSets({
   prices: [
     // default price
     {
-      amount: 500,
+      amount: 5,
       currency_code: "EUR",
       rules: {},
     },
     // prices with rules
     {
-      amount: 400,
+      amount: 4,
       currency_code: "EUR",
       rules: {
         region_id: "reg_123",
       },
     },
     {
-      amount: 450,
+      amount: 4.5,
       currency_code: "EUR",
       rules: {
         city: "krakow",
       },
     },
     {
-      amount: 500,
+      amount: 5,
       currency_code: "EUR",
       rules: {
         city: "warsaw",
@@ -194,7 +194,7 @@ const priceSet = await pricingModuleService.createPriceSets({
       },
     },
     {
-      amount: 200,
+      amount: 2,
       currency_code: "EUR",
       min_quantity: 100,
     },
@@ -232,10 +232,10 @@ const priceSet = await pricingModuleService.createPriceSets({
     const price = {
       id: "<PRICE_SET_ID>",
       is_calculated_price_price_list: false,
-      calculated_amount: 500,
+      calculated_amount: 5,
 
       is_original_price_price_list: false,
-      original_amount: 500,
+      original_amount: 5,
 
       currency_code: "EUR",
 
@@ -299,10 +299,10 @@ const priceSet = await pricingModuleService.createPriceSets({
     const price = {
       id: "<PRICE_SET_ID>",
       is_calculated_price_price_list: false,
-      calculated_amount: 500,
+      calculated_amount: 5,
 
       is_original_price_price_list: false,
-      original_amount: 500,
+      original_amount: 5,
 
       currency_code: "EUR",
 
@@ -353,7 +353,7 @@ const priceSet = await pricingModuleService.createPriceSets({
             items: [
               {
                 id: "item_1",
-                quantity: 200,
+                quantity: 2,
                 // assuming the price set belongs to this variant
                 variant_id: "variant_1",
                 // ...
@@ -375,10 +375,10 @@ const priceSet = await pricingModuleService.createPriceSets({
     const price = {
       id: "<PRICE_SET_ID>",
       is_calculated_price_price_list: false,
-      calculated_amount: 200,
+      calculated_amount: 2,
 
       is_original_price_price_list: false,
-      original_amount: 200,
+      original_amount: 2,
 
       currency_code: "EUR",
 
@@ -433,12 +433,12 @@ const priceSet = await pricingModuleService.createPriceSets({
       type: "sale",
       prices: [
         {
-          amount: 400,
+          amount: 4,
           currency_code: "EUR",
           price_set_id: priceSet.id,
         },
         {
-          amount: 450,
+          amount: 4.5,
           currency_code: "EUR",
           price_set_id: priceSet.id,
         },
@@ -466,10 +466,10 @@ const priceSet = await pricingModuleService.createPriceSets({
     const price = {
       id: "<PRICE_SET_ID>",
       is_calculated_price_price_list: true,
-      calculated_amount: 400,
+      calculated_amount: 4,
 
       is_original_price_price_list: false,
-      original_amount: 500,
+      original_amount: 5,
 
       currency_code: "EUR",