[BLD-259] Playground, Portal: Add revalidation for API Reference page (#8022)

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## PR-Codex overview
This PR updates the metadata and content for the API reference pages in the `portal` and `playground-web` applications, enhancing the descriptions and titles to better reflect the purpose of the APIs. It also introduces a revalidation period for both pages.

### Detailed summary
- Updated `metadata` in `apps/portal/src/app/reference/page.tsx`:
  - Changed `title` from "API Reference" to "thirdweb API Reference".
  - Changed `description` from "Complete REST API reference for all thirdweb services" to "A Unified interface for Web3 development".
- Added `revalidate` property with value `3600` in `apps/portal/src/app/reference/page.tsx`.
- In `apps/playground-web/src/app/reference/page.tsx`:
  - Imported `ScalarApiReference` and `createMetadata`.
  - Added `metadata` with `title` "thirdwebAPI Reference" and `description` "A Unified interface for Web3 development".
  - Added `revalidate` property with value `3600`.

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Author: MananTank

apps/playground-web/src/app/reference/page.tsx

@@ -1,7 +1,15 @@
-import { ScalarApiReference } from "../../components/blocks/scalar-api/ScalarClient";
+import { ScalarApiReference } from "@/components/blocks/scalar-api/ScalarClient";
+import { createMetadata } from "@/lib/metadata";
 
 export default async function ReferencePage() {
   const responses = await fetch("https://api.thirdweb.com/openapi.json");
   const spec = await responses.json();
   return <ScalarApiReference spec={spec} />;
 }
+
+export const metadata = createMetadata({
+  title: "thirdwebAPI Reference",
+  description: "A Unified interface for Web3 development",
+});
+
+export const revalidate = 3600;

apps/portal/src/app/reference/page.tsx

@@ -3,11 +3,11 @@ import { ScalarApiReference } from "./ScalarClient";
 
 export const metadata = createMetadata({
   image: {
-    title: "API Reference",
+    title: "thirdweb API Reference",
     icon: "thirdweb",
   },
   title: "thirdweb API Reference",
-  description: "Complete REST API reference for all thirdweb services",
+  description: "A Unified interface for Web3 development",
 });
 
 export default async function ApiReferencePage() {
@@ -19,3 +19,5 @@ export default async function ApiReferencePage() {
     </div>
   );
 }
+
+export const revalidate = 3600;