Keyboard Cursor Controls

It's nice to move the mouse, but that requires a hand on the LHS of the KB.

It would be better to also be able to input single key "Left, Right, Up, Down" etc from the `Interrupt` space.

Unsure how this would work. It may require a remapping of Mouse keys to QWER and KB keys to ASDF.

So this is a configuration issue, which is surely lacking anyway.

未指定任何文件或测试。首先定位 Interrupt 输入处理以及现有的鼠标和键盘配置路径，然后在进行更改之前明确所需的按键映射；当约定的单键光标控制能够正常工作且不与鼠标控制冲突时，即视为完成。

由索引模型根据 Issue 内容生成。