docs: fixed keywords usage in some pages (#14140)

* docs: fixed keywords usage in some pages

* fix vale error

* fix vale error

www/apps/cloud/app/emails/page.mdx

@@ -16,6 +16,16 @@ import { ChevronUpDown } from "@medusajs/icons"
 
 export const metadata = {
   title: `Medusa Emails`,
+  keywords: [
+    "email",
+    "mail",
+    "medusa mail",
+    "transactional email",
+    "marketing email",
+    "email service",
+    "cloud email",
+    "medusa emails",
+  ],
 }
 
 # {metadata.title}

www/apps/cloud/app/sign-up/page.mdx

@@ -1,3 +1,11 @@
+---
+keywords:
+  - deploy
+  - deployment
+  - production
+  - cloud
+---
+
 export const metadata = {
   title: `Sign Up for Cloud`,
   keywords: ["deploy", "deployment", "production", "cloud"],

www/apps/resources/app/how-to-tutorials/tutorials/saved-payment-methods/page.mdx

@@ -20,6 +20,13 @@ import { Prerequisites, Card, InlineIcon } from "docs-ui"
 
 export const metadata = {
   title: `Use Saved Payment Methods During Checkout`,
+  keywords: [
+    "saved payment methods",
+    "stripe",
+    "payment provider",
+    "checkout",
+    "nextjs",
+  ]
 }
 
 # {metadata.title}

www/packages/docs-ui/src/components/TechArticleJsonLd/index.tsx

@@ -9,6 +9,7 @@ import { usePathname } from "next/navigation"
 export const TechArticleJsonLd = () => {
   const {
     config: { baseUrl, basePath, description: configDescription, titleSuffix },
+    frontmatter,
   } = useSiteConfig()
   const pathname = usePathname()
   const { isBrowser } = useIsBrowser()
@@ -36,7 +37,8 @@ export const TechArticleJsonLd = () => {
         proficiencyLevel: "Expert",
         author: "Medusa",
         genre: "Documentation",
-        keywords: "medusa, ecommerce, open-source",
+        keywords:
+          frontmatter.keywords?.join(", ") || "medusa, ecommerce, open-source",
         url: `${baseLink}${pathname}`,
       })