[Feature Request] Allow user override for Fable model selection when blocked by safety policies

Question

**Bug Description**
I specifically requested Fable 5 for the last few hours of availability to run a security audit and produce a report on my local system's OS. The overly broad cybersecurity block for Fable 5 dropped me back to Opus 4.8. I don't mind Opus, but I wanted to take advantage of Fable's much stronger threat and security analysis, reporting, and mitigation capabilities so that I can make my own system more resilient and secure.

**Environment Info**
- Platform: linux
- Terminal: kitt