[Portal] Docs: adds SiteEmbed and SiteLink to docs (#5334)

CNCT-2266

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## PR-Codex overview
This PR adds a new section titled "Advanced" to the sidebar in the `sidebar.tsx` file, which includes links to UI components. This enhances the navigation structure, providing users with easier access to specific features.

### Detailed summary
- Added a new section `Advanced` to the sidebar.
- Set `isCollapsible` to `false` for the `Advanced` section.
- Included a `links` array under `Advanced` with a link to `UI Components`.
- Mapped `SiteEmbed` and `SiteLink` to create individual links with names, hrefs, and icons.

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Author: gregfromstl

apps/portal/src/app/react/v5/sidebar.tsx

@@ -391,6 +391,21 @@ export const sidebar: SideBar = {
       ],
     },
     { separator: true },
+    {
+      name: "Advanced",
+      isCollapsible: false,
+      links: [
+        {
+          name: "UI Components",
+          links: ["SiteEmbed", "SiteLink"].map((name) => ({
+            name,
+            href: `${slug}/${name}`,
+            icon: <CodeIcon />,
+          })),
+        },
+      ],
+    },
+    { separator: true },
     {
       name: "Migrate from v4",
       href: `${slug}/migrate`,