Enhancements to Studio authentication

[lvca]

Discussed in https://github.com/ArcadeData/arcadedb/discussions/867

^{Originally posted by vic0824 February 18, 2023} I have a couple of related ideas for enhancing the Studio authentication:

1. currently the authentication status (i.e. whether a user is authenticated in Studio) is lost after a page reload; this might be intentional or it might be simply a side-effect of the design choice of using the globalCredentials global JavaScript variable; storing the information in the session storage is a possible enhancement that would eliminate the need to repeat the login after a page reload and it would open up interesting possibilities (see bullet 2 below)
2. I think it would be useful to allow the front-end of a custom http plugin to share the authentication with Studio, i.e. if the user has logged in to Studio, he is considered also logged in the custom plugin, and vice versa if the user has logged in to the custom plugin, he is considered logged in also in Studio

I think feature 2 could be implemented rather easily if feature 1 is implemented, but there could be other ways of doing it that are better from a different point of view. Comments and suggestions are welcome.