Hello,
I haven't come across any GH plugin that would do that for you in a reliable way, as those strategies are quite complicated and also do not fit that well into the GH way of programming.
Don't get me wrong, it's definitely possible to create milling strategy for individual use cases in GH and you can save great amounts of time through mass customization opposed to CAM software. But there isn't a script that will work well for "all" geometries, like in CAM software where you define the stock, the geometry, set a few parameters and get a working solution.
For "generic" CAM work we usually use Fusion 360, as it has got a nice interface and doesn't cost much (free for EDU). There is a Fusion 360 component in KUKA|prc, you can right-click it to export a postprocessor. Code generated through this PP can then be imported into GH and e.g. combined with your parametric geometry. Note that you need an additional "orientation" point as you get 5-axis G-code out of Fusion, that does not define the rotation around the tool axis!
Best,
Johannes