chore: align actions and icons in all pages

[dariofaccin]

Description

This PR introduces the following improvements and modifications in NMS UI:

• actions are icons
• refresh buttons and Log out use Vanilla icon
• modals in Users are aligned in appearance to other modals

Screenshots

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.
• I have added tests that validate the behaviour of the software.
• I validated that new and existing unit tests pass locally with my changes.
• Any dependent changes have been merged and published in downstream modules.