Rate

// ── Rate ──
pub fn buildRate(scope: *ui.Scope, cx: *ui.Cx) anyerror!*ui.Node {
    const a = cx.allocator;
    const c = try col(cx, 16);
    const r1 = try W.Rate(.{ .count = 5, .value = 3 }).mount(scope, cx);
    try c.appendChild(a, try label(cx, "value 3 / 5"));
    try c.appendChild(a, r1.wrapper);
    const r2 = try W.Rate(.{ .count = 5, .value = 4, .disabled = true }).mount(scope, cx);
    try c.appendChild(a, try label(cx, "readonly value 4"));
    try c.appendChild(a, r2.wrapper);

    // ── count 变体 ──
    const r3 = try W.Rate(.{ .count = 10, .value = 7 }).mount(scope, cx);
    try c.appendChild(a, try label(cx, "count 10, value 7"));
    try c.appendChild(a, r3.wrapper);

    // ── size 变体 ──
    try c.appendChild(a, try label(cx, "Sizes (16 / 24 / 36)"));
    const sizes_row = try row(cx, 24);
    inline for (.{ 16, 24, 36 }) |sz| {
        const rn = try W.Rate(.{ .count = 5, .value = 3, .size = @as(f32, sz) }).mount(scope, cx);
        try sizes_row.appendChild(a, rn.wrapper);
    }
    try c.appendChild(a, sizes_row);
    return c;
}