Docs sidebar active scroll needs a DOM current query

Problem

The docs sidebar can look visually correct while still opening deep pages with the active item hidden below the fold. A ref attached through next/link is not the most reliable source for active-scroll handoff in this docs sidebar.

Symptoms

/docs/components/ai-menu rendered the correct active AI Menu link, but the sidebar stayed at scrollTop: 0.
Browser inspection showed the active link around 3000px below the top of the nav while the sidebar viewport ended around 720px.
Running the same scroll calculation manually in the browser moved the sidebar correctly, so the scroll math was not the problem.

What Didn't Work

Passing a React ref through the exact active Link and calling scrollIntoView. The active DOM node existed, but the effect did not reliably get the element and the sidebar did not move.
Letting scrollIntoView choose the scroll container. The docs page has a nested sidebar scroller, so relying on the browser to pick the right container is fragile.

Solution

Mark the real sidebar scroll container in the docs layouts:

tsx

<div className="scrollbar-hide h-full overflow-auto" data-docs-sidebar-scroll>
  <DocsNav sidebarNav={sidebarNav} />
</div>

In DocsNav, keep a ref on the nav root and query the rendered current link after route changes:

tsx

const activeElement = navElement?.querySelector<HTMLAnchorElement>(
  'a[aria-current="page"]'
);

Then scroll the nearest [data-docs-sidebar-scroll] container explicitly:

tsx

const offset =
  itemRect.top -
  areaRect.top -
  scrollArea.clientHeight / 2 +
  itemRect.height / 2;

scrollArea.scrollTo({
  top: Math.max(0, scrollArea.scrollTop + offset),
});

Why This Works

aria-current="page" is the rendered truth for the exact active route. Querying that DOM state avoids depending on ref forwarding through a framework link component, and scrolling the marked container avoids accidentally moving the document body or doing nothing when the active link sits inside a nested overflow area.

Prevention

For docs navigation, make aria-current the browser-verifiable active route marker.
When auto-scrolling an active nav item, mark the intended scroll container and scroll it directly.
Browser-test deep docs routes, not just /docs, after sidebar changes.
Verify both the visual style and the scroll state: active item visible, nonzero sidebar scrollTop, and no full-page scroll jump.