Compliance frame can't be called "Default or default"

What does this MR do and why?

This MR prohibits use of "default" as compliance framework name both on frontend and backend side

Additionally on frontend (and we're ok with this being only frontend validation) usage of "default" in current user locale is also prohibited

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

English locale:

Ukrainian locale:

How to set up and validate locally

1. Navigate to a top-level group
2. Open the Secure ▶ Compliance center
3. Add framework and attempt to use "default" (any case) as name
4. Observe error

Numbered steps to set up and validate the change are strongly suggested.

Related to #450986