Create utils package

Over time our various utils directories and files have caused quite a lot of code duplication (e.g. `arrayOf` is one of those examples). I'd propose to create a package (public or private) for that called `@semapps/frontend-utils` and `@semapps/backend-utils`.

Dou you have any objections or concerns?

Begin by inventorying the existing utils directories and files, including arrayOf, and determine the package boundaries and public/private choice. Done is a documented decision and an agreed implementation scope for @semapps/frontend-utils and @semapps/backend-utils; the issue names no tests or entry point.

Written by the indexing model from the issue text.