WIP: Less intrusive system note - 2nd iteration

What does this MR do?

This MR is the second iteration of #19797 (closed).

Are there points in the code the reviewer needs to double check?

Yes we need to double check if this MR does not break anything in frontend as it is reused in many places

Why was this MR needed?

Making system note less intrusive by adding icons and other refactoring in backend described in issue #24784 (closed)

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

#19797 (closed), #24784 (closed), #23129 (closed)