left/right arrow keyboard buffer

### Describe the feature or problem you'd like to solve

When moving the cursor in a prompt or on the `other` part of a multiple choice, the cursor doesn't stop when the finger is raised from the left/right key but the keeps going until the keyboard buffer is completely flushed.

### Proposed solution

stop the editor cursor movement (ignore the rest of the buffer) when the user raises his finger from the key

### Example prompts or workflows

_No response_

### Additional context

_No response_

首先定位 prompt 编辑器和多项选择“other”输入的处理逻辑，然后跟踪左右键事件是如何被缓冲的。完成的标准是松开按键时光标移动停止，并且忽略缓冲区中剩余的任何移动；在所描述的两种工作流中都进行验证。

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