Skeleton

// ── Skeleton ──
pub fn buildSkeleton(scope: *ui.Scope, cx: *ui.Cx) anyerror!*ui.Node {
    const a = cx.allocator;
    const c = try col(cx, 12);
    // 同 spinner：框到骨架图形本身，避开标题/描述文字的像素。
    c.meta.ownership.meta.test_id = "story.skeleton.col";
    try c.appendChild(a, try W.Skeleton(.{ .variant = .text, .width = 280, .height = 14 }).mount(scope, cx));
    try c.appendChild(a, try W.Skeleton(.{ .variant = .text, .width = 200, .height = 14 }).mount(scope, cx));
    try c.appendChild(a, try W.Skeleton(.{ .variant = .circular, .width = 48, .height = 48 }).mount(scope, cx));
    try c.appendChild(a, try W.Skeleton(.{ .variant = .rectangular, .width = 280, .height = 80 }).mount(scope, cx));
    return c;
}