[SandObserver]

Summary

• Replace the 83-line Contributor Covenant 2.1 in CODE_OF_CONDUCT.md with 8 lines: be civil, GitHub's Community Guidelines apply to issues, pull requests and discussions here, and the reporting address stays.
• The removed text restated conduct rules GitHub already enforces on this platform, and committed the maintainer to a four-stage enforcement ladder (correction, warning, temporary ban, permanent ban) that this project has no intention of running.
• Existing links in README.md and CONTRIBUTING.md point at the file itself and are unaffected. GitHub still detects the file for the community profile.

Testing
All green. No new tests: documentation only. Verified the linked Community Guidelines URL returns 200.

Checklist

• Stays within the project constraints: one container, no runtime dependencies, no build step (see CONTRIBUTING.md).
• Tests added or updated for new logic, and the full suite, lint, and typechecks pass.
• Docs updated if behavior or configuration changed.
• CHANGELOG.md updated under Unreleased if the change is user-visible.