feat(deeplink): jump from banner/rank list to the exact post in All Materials

- FigmaBanner: route same-app linkUrl through SPA navigation so the stream's
  scroll-to-post runs without a full reload; defer pointer capture until a real
  drag starts, fixing plain clicks being swallowed by setPointerCapture
- PopularRankList: rank rows navigate straight to /browse?sort=popular&post=<id>
- MessageStream: ?post= deep links jump directly to the target instead of
  resetting to the top and animating through the stream
- ScrollToTop: skip the top-reset for ?post= navigations so the target page
  handles its own alignment

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/components/messageStream/MessageStream.tsx

@@ -121,12 +121,14 @@ export function MessageStream({ scope }: MessageStreamProps) {
         "(prefers-reduced-motion: reduce)",
       ).matches;
 
-      // Show a deliberate "from top to target" transition when opening a card
-      // from Home. The later auto re-alignments are intentionally delayed so
-      // they don't interrupt the visible smooth scroll animation.
-      window.scrollTo({ top: 0, left: 0, behavior: "auto" });
+      // Query deep-links (`?post=<id>`) usually come from Home cards/list rows.
+      // Keep that navigation stable by jumping directly to the target instead
+      // of first resetting to the top and then animating through the stream.
+      // Legacy hash links can still use the visible smooth scroll.
       window.requestAnimationFrame(() =>
-        scrollToTarget(prefersReducedMotion ? "auto" : "smooth"),
+        scrollToTarget(
+          queryTargetPostId || prefersReducedMotion ? "auto" : "smooth",
+        ),
       );
 
       // Media above the target can finish loading after the first scroll and