The brand's voice motif — vertical rounded bars. Animates only while `active` (recording).

```jsx
const { Waveform } = window.DuduDesignSystem_2e0172;
<Waveform active height={26} />                       // 录音中，品牌蓝
<Waveform color="#7C9BFF" active />                   // 深色浮层内用亮蓝
<Waveform color="rgba(255,255,255,.9)" bars={8} />    // 静态装饰
```
