please don't take this as a boast, it is a genuine cry for help and ideas

my dd is coming up 3 and is already reading and starting to write, names countries on the globe, planets in the solar system, uses latin names for body parts, completes 25 piece puzzles, knows all the shapes we can think of including 3d ones and the other day she asked me if i know what onomatopoeia is and when i said no she gave me an explanation.

when she isn't learning or engrossed in role play or my attention isn't 100% focussed on her she is a little madam, she jumps on furniture, screams and shouts and becomes destructive.

the thing is that i have no idea what i should be encouraging her to learn or where to go from here, there is no local support that i have found yet, her nursery where she does 10 hours per week aren't able to do anything academic and her HV is useless.

i am seriously starting to tear my hair out at times, i want to encourage what she has naturally without pushing her but just don't know what i am supposed to be doing

What about starting a homeschool program where you can tailor it to her needs? You can order lots of things online for her to do, little projects, reading and writing practice, math and so on.

Who is teaching her the things she already knows? I mean who taught her what a onomatopoeia was?

I believe I was a little like this and knew how to read etc when I started nursery. I know mum found one of the most useful things was teaching me to tell the time and have an awareness of time so she could say I'll be with you in 10min if you are quiet or 20 if you keep pestering...
Also she used to set me challenges to do my jigsaws upside down - they take much longer without the pictures!!
Going on walks to make me physically tired but having me running all over the place looking for objects in different shapes/colours and then teaching me different types of plants so I had to find for example an acorn, an oak tree leaf, a sycamore leaf etc etc
Keeping a diary so I had to draw a picture of what we had done the day before and then write/have written a sentence underneath...

Maybe it's time to start getting her thinking critically about the books she's reading? what about getting her to give you a little "book report" where she has to tell you what happens in the book, if she liked it, why or why not and draw a picure of her favourite part?
Scavenger hunts - go around the house and write down/draw a picture of one thing from each colour of the rainbow, or that begins with each letter of the alphabet, or that comes in sets of twos, etc.
Also sounds like she's more than ready for simple maths. Fractions could be good because she's got access to things like measuring cups and spoons, blocks, etc at home and you can work that into things like recipes - cooking and baking together.
If she's already learning geography, build on it. Get her to do "Special Investigations" where she has to use an atlas or the internet to figure out where different mountain ranges or rivers are. Get her to find out what sort of things people eat in different countries and report it back to you. What do they wear? What language do they speak? etc.
To get time to yourself, I think you have to set her off on these little missions. Always get her to draw or write her discoveries and that will give you even more time!
Good luck!

Just wanted to add that you won't be pushing her if you follow her curiousity and just let her explore things a little deeper everytime.
One thing that I've found when working with very bright kids is that they do need the proper boundaries set out for them with social behaviour, as well. Sometimes more so than regular kids because they are used to being off alone bythemselves - out ahead of the pack and they don't get the pack rules, as well, if you know what I mean? Definitely encourage imagination and investigation, but she shouldn't think it's okay to be destructive if she's bored. She's intelligent enough to have manners, rules and consequences explained to her.
I say this not to criticize, but because it can make things so much easier when it comes time to fit in and get along with the other kids. That can be a challenge for the gifted ones. It can be lonely!