feat(web): scroll the failed server card into view on connection failure (#1621)

Opening the monitoring column on a failed connection reflows the server
grid to fewer/narrower columns, which can push the failed card below the
fold. Scroll it into view so the red-bordered card is visible without
hunting for it.

- ServerCard scrolls itself into view on the disconnected→errored
  transition (mirrors the freshly-added highlight scroll), deferred
  ~320ms so the column open + grid reflow settle first — otherwise
  scrollIntoView targets the card's pre-reflow position. Guarded by a ref
  so it fires once per failure and won't fight a user who scrolls away.

Verified live: the failed `time` card scrolls fully into view after the
column opens. Full `npm run ci` passes.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BrihGWcrM9JGRyu41nzZYw

clients/web/src/components/groups/ServerCard/ServerCard.test.tsx

@@ -414,5 +414,61 @@ describe("ServerCard", () => {
         container.querySelector('[data-variant="highlighted"]'),
       ).toBeNull();
     });
+
+    it("scrolls the card into view on the errored transition", () => {
+      vi.useFakeTimers();
+      const scrollIntoView = vi.fn();
+      const orig = Element.prototype.scrollIntoView;
+      Element.prototype.scrollIntoView = scrollIntoView;
+      try {
+        const { rerender } = renderWithMantine(
+          <ServerCard {...baseProps} connection={disconnected} />,
+        );
+        // No scroll while not errored.
+        vi.advanceTimersByTime(1000);
+        expect(scrollIntoView).not.toHaveBeenCalled();
+
+        // Becoming errored schedules a deferred scroll (past the column open).
+        rerender(
+          <ServerCard {...baseProps} connection={disconnected} errored />,
+        );
+        expect(scrollIntoView).not.toHaveBeenCalled();
+        vi.advanceTimersByTime(320);
+        expect(scrollIntoView).toHaveBeenCalledTimes(1);
+
+        // A further re-render while still errored does not scroll again (so it
+        // won't fight a user who scrolled away).
+        rerender(
+          <ServerCard
+            {...baseProps}
+            name="Renamed"
+            connection={disconnected}
+            errored
+          />,
+        );
+        vi.advanceTimersByTime(1000);
+        expect(scrollIntoView).toHaveBeenCalledTimes(1);
+      } finally {
+        Element.prototype.scrollIntoView = orig;
+        vi.useRealTimers();
+      }
+    });
+
+    it("does not scroll when mounted already errored (no transition)", () => {
+      vi.useFakeTimers();
+      const scrollIntoView = vi.fn();
+      const orig = Element.prototype.scrollIntoView;
+      Element.prototype.scrollIntoView = scrollIntoView;
+      try {
+        renderWithMantine(
+          <ServerCard {...baseProps} connection={disconnected} errored />,
+        );
+        vi.advanceTimersByTime(1000);
+        expect(scrollIntoView).not.toHaveBeenCalled();
+      } finally {
+        Element.prototype.scrollIntoView = orig;
+        vi.useRealTimers();
+      }
+    });
   });
 });