refactor current mobx usage

Since I'm a newb in NextJs I didn't know about hydration and the performance issues that might occure with the current setup. This issue will refactor it all to be done "properly". 

[store pattern mobx](https://dev.to/ivandotv/mobx-root-store-pattern-with-react-hooks-318d)
[mobx and SSR](https://dev.to/ivandotv/mobx-server-side-rendering-with-next-js-4m18)

related issues:
#45 