docs: update examples in sendgrid guide (#12504)

* initial

* docs: update examples in sendgrid guide

* add note for local file module

www/apps/resources/app/infrastructure-modules/notification/send-notification/page.mdx

@@ -14,11 +14,11 @@ export const metadata = {
 
 # {metadata.title}
 
-In this guide, you'll learn how to send a notification using the Notification Module.
+In this guide, you'll learn about the different ways to send notifications using the Notification Module.
 
-## Use the Create Method
+## Using the Create Method
 
-In your resource, such as a subscriber, resolve the Notification Module's main service and use its `create` method:
+In your resource, such as a [subscriber](!docs!/learn/fundamentals/events-and-subscribers), resolve the Notification Module's main service and use its `create` method:
 
 export const highlights = [
   ["12", "notificationModuleService", "Resolve the Notification Module."],
@@ -56,7 +56,7 @@ export default async function productCreateHandler({
     container.resolve(Modules.NOTIFICATION)
 
   await notificationModuleService.createNotifications({
-    to: "shahednasser@gmail.com",
+    to: "user@gmail.com",
     channel: "email",
     template: "product-created",
     data,
@@ -103,3 +103,78 @@ The `create` method accepts an object or an array of objects having the followin
 />
 
 For a full list of properties accepted, refer to [this guide](/references/notification-provider-module#create).
+
+---
+
+## Using the sendNotifcationStep
+
+If you want to send a notification as part of a workflow, You can use the [sendNotifcationStep](!resources!/references/medusa-workflows/steps/sendNotificationsStep) in your workflow.
+
+For example:
+
+```ts title="src/workflows/send-email.ts"
+import { createWorkflow } from "@medusajs/framework/workflows-sdk"
+import { 
+  sendNotificationsStep, 
+  useQueryGraphStep,
+} from "@medusajs/medusa/core-flows"
+
+type WorkflowInput = {
+  id: string
+}
+
+export const sendEmailWorkflow = createWorkflow(
+  "send-email-workflow",
+  ({ id }: WorkflowInput) => {
+    const { data: products } = useQueryGraphStep({
+      entity: "product",
+      fields: [
+        "*",
+        "variants.*",
+      ],
+      filters: {
+        id,
+      },
+    })
+
+    sendNotificationsStep({
+      to: "user@gmail.com",
+      channel: "email",
+      template: "product-created",
+      data: {
+        product_title: product[0].title,
+        product_image: product[0].images[0]?.url,
+      },
+    })
+  }
+)
+```
+
+For a full list of input properties accepted, refer to the [sendNotifcationStep](!resources!/references/medusa-workflows/steps/sendNotificationsStep) reference.
+
+You can then execute this workflow in a subscriber, API route, or scheduled job.
+
+For example, you can execute it when a product is created:
+
+```ts title="src/subscribers/product-created.ts"
+import type {
+  SubscriberArgs,
+  SubscriberConfig,
+} from "@medusajs/framework"
+import { sendEmailWorkflow } from "../workflows/send-email"
+
+export default async function productCreateHandler({
+  event: { data },
+  container,
+}: SubscriberArgs<{ id: string }>) {
+  await sendEmailWorkflow(container).run({
+    input: {
+      id: data.id,
+    },
+  })
+}
+
+export const config: SubscriberConfig = {
+  event: "product.created",
+}
+```