Show empty architecture during cluster provisioning

[torchiaf]

Summary

Fixes #10831

Occurred changes and/or fixed issues

Technical notes summary

We want to show empty character during cluster provisioning phase.

Areas or cases that should be tested

Areas which could experience regressions

Screenshot/Video

Dashboard page

Clusters management page

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
• The PR has a Milestone
• The PR template has been filled out
• The PR has been self reviewed
• The PR has a reviewer assigned
• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
• The PR has reviewed with UX and tested in light and dark mode, or there are no UX changes