Define programming standards for React

[giemic8]

Why we need this ticket

We currently have different approaches to how the project is structured. For example, we have some components defined in an index.tsx and most of them are called .tsx.
The components are also created differently. Sometimes with 'export const = ()' and sometimes with 'export function ()'.

TODO in this ticket

Check what are development standards in React and define standards for trufos.