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## Summary by cubic
Adds a GitHub Action to detect and comment on potential duplicate issues
when a new issue is opened. This reduces triage time and keeps issue
lists clean.

- **New Features**
- Adds .github/workflows/duplicate-issues.yml triggered on issues:
opened.
- Uses opencode with Anthropic Claude Sonnet 4 to scan existing issues
and comment with links if duplicates are likely; stays silent otherwise.
- Runs with minimal permissions; allows gh issue commands and denies
webfetch.

- **Migration**
- Create the ai-bots environment and add the ANTHROPIC_API_KEY secret
(GITHUB_TOKEN is provided by GitHub).

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