The first question I'd ask is why on earth you wanted to do that.
Technically you can run any code with jelly, it's just a case of laboriously working out all the objects you need and the methods to call on them, and then using a syntax that would make you tear your hair out. So technically yes, you can get the ScriptManager instance and run a groovy script.
If you explained why you wanted to do this I could probably give some more targeted advice.
my first thought was i wanted to run it as a service. I saw "run jelly script" as a built in option. I actually found something you wrote i think that offers up this class:
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