Hide unused helper marks on selection cards and modal section labels until tooltip behavior ships.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/CardStack.test.jsx

@@ -65,6 +65,21 @@ describe("CardStack Component", () => {
     expect(screen.getAllByText("Option C").length).toBeGreaterThanOrEqual(1);
   });
 
+  test("hides helper icons on compact, expanded, and single-stack cards", () => {
+    const { unmount } = render(
+      <CardStack cards={SAMPLE_CARDS} expanded={false} />,
+    );
+    expect(screen.queryByText("?")).not.toBeInTheDocument();
+    unmount();
+
+    const expanded = render(<CardStack cards={SAMPLE_CARDS} expanded={true} />);
+    expect(screen.queryByText("?")).not.toBeInTheDocument();
+    expanded.unmount();
+
+    render(<CardStack cards={SAMPLE_CARDS} layout="singleStack" />);
+    expect(screen.queryByText("?")).not.toBeInTheDocument();
+  });
+
   test("expanded tiles use the compact 142px CardSelection height", () => {
     render(<CardStack cards={SAMPLE_CARDS} expanded={true} />);