Possibility to add Tags to FlowFuse Users

### Description

Please add the possibility to add Tags (multiple) to FlowFuse users.
These Tags should then be part of the msg._client.user object in NodeRED so flows can make use of them.
Such a system could be used to add relevant information to a user account, and have flows act upon that information.

### Which customers would this be available to

Team + Enterprise Tiers (EE)

### Have you provided an initial effort estimate for this issue?

I am not a FlowFuse team member