feat: add autotype flags

[carafelix]

I would like to see how fast is to type at, for example, 200 wpm, so adding a flag like

mitype -auto 200

should play a replay of typing a text at flat 200wpm. Maybe even add some more options for curve fitting the replay speed

mitype -auto -curve cubic-bezier 100 150 80 120 200

or some type of granular control over the typing speed, like noise or randomness whatever

[welcome]

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