Add reputation probation reinstatement guard

[AlonePenguin]

Summary

• Adds a self-contained reputation probation and reinstatement guard for issue Community & User Reputation System #15.
• Validates minimum probation windows, open appeal blockers, remediation evidence, independent reviewer quorum, public-redacted reinstatement receipts, probation-window reputation deltas, and capped re-entry before profile reputation, badges, and leaderboards resume.
• Includes synthetic clean/risky packets plus JSON, Markdown, SVG, and MP4 reviewer artifacts.

Non-overlap

This is a post-moderation re-entry/probation control, separate from existing broad reputation ledgers, endorsement rings, review calibration, badge renewal/decay, leaderboard eligibility, civility checks, correction impact, peer-review recertification, workload equity, profile credit consent, and abuse detection submissions.

Verification

• npm run check
• npm test
• npm run demo
• npm run verify-video
• git diff --check
• git diff --cached --check

/claim #15