[Bug] Claude posts external API actions without explicit confirmation despite CLAUDE.md restrictions

**Bug Description**
Title: Claude posted GitHub comments on my behalf without approval

Description:

Claude was helping me handle code review comments on a PR. At the end of one turn it asked "Want me to apply the two fixes and post the replies?". My next message only answered the technical questions about which review comments to fix. I never answered the question about posting.

Claude took that as a yes and posted five review replies on the PR under my GitHub account. I had to delete all five manually.

This is worse because my global CLAUDE.md explicitly says to always stop and ask before making API calls to external services, even in permissive permission modes. Writing comments in my name is exactly the kind of action that needs explicit confirmation.

Expected: when an offer to do something outward-facing goes unanswered, show the drafts and ask again. Only post after a clear yes for that specific action.

Happened on Claude Code with the claude-fable-5 model, 2026-08-31

**Environment Info**
- Platform: darwin
- Terminal: iTerm.app
- Version: 2.1.251
- Feedback ID: 165259f1-9c1f-40b3-9357-4c0720aa08f1

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

No source file or test is named in the report. Start with the Claude Code path that handles proposed GitHub comments and the global CLAUDE.md restriction; reproduce the unanswered-offer flow, then verify that drafts are shown and posting occurs only after a clear confirmation for that action.

由索引模型根据 Issue 内容生成。