docs(docs): add header tabs for Changelog and Appendix pages

apps/docs/components/SourceSidebar.astro

@@ -1,17 +1,14 @@
 ---
 /**
  * The `Sidebar` slot (also the mobile drawer's nav, which defaults to it): a
- * Fumadocs-style content-source selector, then the pinned links, then
- * Blume's own nav tree scoped to the active source (`sources.ts`).
- *
- * The pinned links live here, not in `navigation.featured`: Blume renders
- * featured links above this slot, so the selector could not sit over them.
+ * Fumadocs-style content-source selector, then Blume's own nav tree scoped to
+ * the active source (`sources.ts`).
  *
  * The selector is a `<details>` with Blume's `data-blume-dropdown` light
  * dismiss (outside press, Escape, focus leaving), like its own NavSelector.
  */
 import Icon from "blume/components/Icon.astro";
-import { withBase, withMountedBase } from "blume/components/islands/base-path.ts";
+import { withMountedBase } from "blume/components/islands/base-path.ts";
 import NavTree from "blume/components/layout/NavTree.astro";
 import type { UIStrings } from "blume/core/i18n-ui.ts";
 import { isUnderPath } from "blume/core/navigation.ts";
@@ -26,11 +23,6 @@ interface Props {
   fragmentBase?: string;
 }
 
-const PINNED = [
-  { label: "Changelog", href: "/changelog", icon: "clock" },
-  { label: "Appendix", href: "/appendix", icon: "library" },
-];
-
 const { items, currentRoute, ...tree } = Astro.props;
 
 const active =
@@ -89,25 +81,6 @@ const scoped =
   </div>
 </details>
 
-<nav aria-label="Featured" class="mb-4 border-border border-b pb-4">
-  <ul class="m-0 list-none p-0">
-    {
-      PINNED.map((link) => (
-        <li>
-          <a
-            aria-current={currentRoute === link.href ? "page" : undefined}
-            class="flex items-center gap-2 rounded-[0.65rem] px-2.5 py-1.5 text-muted-foreground text-sm transition-colors hover:bg-muted hover:text-foreground aria-[current=page]:bg-muted aria-[current=page]:text-foreground"
-            href={withBase(link.href)}
-          >
-            <Icon class="shrink-0" name={link.icon} size={14} />
-            <span class="flex-1 truncate">{link.label}</span>
-          </a>
-        </li>
-      ))
-    }
-  </ul>
-</nav>
-
 <NavTree {...tree} currentRoute={currentRoute} items={scoped} />
 
 <script>