[Bug] Anthropic API Error: Overly aggressive safety filtering on legitimate system signal operations

**Bug Description**
I got an "Opus 5 (1M context)'s safeguards flagged this message." "Details: [cyber]" which is a false-positive, I am working on my own systems, and doing development where I am sending signals (SIGBREAK) to a task I own. This should not have been flagged under cyber anything.

**Environment Info**
- Platform: linux
- Terminal: gnome-terminal
- Version: 2.1.267
- Feedback ID: b7638dee-de8b-471d-90a0-a57537c25031

**Errors**
```json
[]
```

Start by reviewing feedback ID b7638dee-de8b-471d-90a0-a57537c25031 and reproducing the report in Linux with gnome-terminal while sending SIGBREAK to an owned task. Done would mean this legitimate system-signal operation is no longer classified as a cyber safety violation.

索引モデルが issue の本文から書いたものです。