voice effect internal api should be tempo sync per param like the bus effects are

[baconpaul]

the way we tempo sync the lfo with envelope rate linear is what makes this hard.

[Andreya-Autumn]

One comment: I have been thinking that FXModControl maybe would work better for the voice-effects anyway, because of the smoothing it applies to the discontinuous shapes. I haven't looked at it enough to figure out how difficult that change would be. But if it would make this easier I could maybe do that first.

[baconpaul]

That's really separate. The change here is temposyncRatio will get an index argument for the parameter is all.