FN-5864: stabilize ChatView skill-menu keyboard assertions

Make the ChatView skill-menu keyboard navigation test wait for async UI updates.

- wrap the highlighted-option assertion after ArrowUp in waitFor to avoid synchronous timing races
- wait for the textarea value update after Enter selection before asserting the chosen skill command

Files changed:
 packages/dashboard/app/components/__tests__/ChatView.test.tsx | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Fusion-Task-Id: FN-5864

Fusion-Task-Lineage: 9f1b3988-7022-415f-8d4b-83b0b3b25dfb

packages/dashboard/app/components/__tests__/ChatView.test.tsx

@@ -1779,12 +1779,14 @@ describe("ChatView", () => {
 
       // Wrap to bottom from the first item.
       fireEvent.keyDown(textarea, { key: "ArrowUp" });
-      expect(screen.getByRole("option", { name: /gamma/i })).toHaveClass(
-        "chat-skill-menu-item--highlighted",
+      await waitFor(() =>
+        expect(screen.getByRole("option", { name: /gamma/i })).toHaveClass(
+          "chat-skill-menu-item--highlighted",
+        ),
       );
 
       fireEvent.keyDown(textarea, { key: "Enter" });
-      expect(textarea).toHaveValue("/skill:gamma ");
+      await waitFor(() => expect(textarea).toHaveValue("/skill:gamma "));
     });
 
     it("supports selecting highlighted skill with Tab", async () => {