feat: Add currency module and remove currency models from region and pricing modules (#6536)

What:
- Creates a new currency module
- Removes currency model from the pricing module
- Removes currency model from region module

packages/currency/src/loaders/initial-data.ts

@@ -0,0 +1,30 @@
+import { ModuleRegistrationName } from "@medusajs/modules-sdk"
+import { ModulesSdkTypes, LoaderOptions } from "@medusajs/types"
+import { defaultCurrencies } from "@medusajs/utils"
+import { Currency } from "@models"
+
+export default async ({
+  container,
+  options,
+}: LoaderOptions<
+  | ModulesSdkTypes.ModuleServiceInitializeOptions
+  | ModulesSdkTypes.ModuleServiceInitializeCustomDataLayerOptions
+>): Promise<void> => {
+  try {
+    const {
+      currencyService_,
+    }: { currencyService_: ModulesSdkTypes.InternalModuleService<Currency> } =
+      container.resolve(ModuleRegistrationName.CURRENCY)
+
+    const normalizedCurrencies = Object.values(defaultCurrencies).map((c) => ({
+      ...c,
+      code: c.code.toLowerCase(),
+    }))
+    const resp = await currencyService_.upsert(normalizedCurrencies)
+    console.log(`Loaded ${resp.length} currencies`)
+  } catch (error) {
+    console.error(
+      `Failed to load currencies, skipping loader. Original error: ${error.message}`
+    )
+  }
+}