feat(affiliates): add gas rebate 71 for July 2026

[md0x]

Summary

• Add the July 2026 VotingV2 monthly gas rebate artifact for rebate 71 (blocks 25433939–25656293, contiguous with rebate 70).
• Include the generated audit markdown for the rebate run.
• First full month with the delegate exclusion list applied; excluded voter and rebate totals are reported in the audit.

Validation

• Parsed packages/affiliates/gas-rebate/rebates/Rebate_71.json with jq -e and confirmed the payout map sums to the reported total.
• Confirmed the audit report marks validation as passed and reports no anomalies.