use alert for the system message

[mawinter69]

the alert will take care of the proper coloring and is theme aware. convert the colors to the alert levels, maps red -> danger orange -> warning lightyellow -> info

there is a new level success now.

This change might break CasC when a systemMessage is configured in CasC. Use

configuration-as-code:
  deprecated: warn

or change color to level according to above mapping.

Testing done

### Submitter checklist
- [x] Make sure you are opening from a **topic/feature/bugfix branch** (right side) and not your main branch!
- [x] Ensure that the pull request title represents the desired changelog entry
- [x] Please describe what you did
- [ ] Link to relevant issues in GitHub or Jira
- [ ] Link to relevant pull requests, esp. upstream and downstream changes
- [ ] Ensure you have provided tests - that demonstrates feature works or fixes the issue