feat(#103): Backup and disaster recovery system

[Agbasimere]

🚀 Pull Request

📋 Description

Adds a backup and disaster recovery system: on-chain backup manifests, scheduling, integrity verification, recovery records with RTO tracking, and audit trail. Indexer persists backup/recovery events and exposes APIs for manifests, recoveries, RTO metrics, and audit trail.

🔗 Related Issue(s)

• Closes Build Advanced Backup and Disaster Recovery System #103

🎯 Type of Change

• ✨ New feature (non-breaking change that adds functionality)
• 🐛 Bug fix (non-breaking change that fixes an issue)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 📚 Documentation update
• 🔧 Tooling/Infrastructure
• 🧪 Test improvements
• 🔒 Security fix
• ♻️ Refactoring (no functional changes)
• ⚡ Performance improvements

📝 Changes Made

• Contract: New backup.rs – create_backup, verify_backup, schedule_backup, record_recovery; types (BackupManifest, RecoveryRecord, RtoTier); events (BackupCreated, BackupVerified, RecoveryExecuted); audit logging for all actions
• Contract: New storage keys (BACKUP_MANIFESTS, BACKUP_SCHEDULES, RECOVERY_RECORDS, etc.); OperationType extended for backup/verify/recovery
• Indexer: Entities BackupManifestRecord, RecoveryRecordEntity; backup.events.ts; event handlers for backup/DR events
• Indexer: BackupModule – BackupService (manifests, recoveries, RTO metrics, audit trail), BackupController; GET /backup/manifests, /recoveries, /rto-metrics, /audit-trail
• Tests: test_backup_dr.rs (contract registration, RtoTier)

🧪 Testing

✅ Pre-Merge Checklist (Required)

• 🧪 Unit Tests: I have run cargo test --lib and all tests pass
• 🔨 Debug Build: I have run cargo build and the project builds successfully
• 🎯 WASM Build: I have run cargo build --target wasm32-unknown-unknown --release and WASM builds successfully
• 📝 Code Formatting: I have run cargo fmt --all -- --check and code is properly formatted
• 🔍 Clippy Lints: I have run cargo clippy and there are no new warnings

📋 Test Results

🔍 Review Checklist

📝 Code Quality

• My code follows the project's style guidelines
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings or errors

🧪 Testing Requirements

• I have added/updated tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Integration tests have been updated (if applicable)

📚 Documentation

• I have updated the documentation accordingly
• I have updated the CHANGELOG (if applicable)

🔒 Security

• I have not committed any secrets, keys, or sensitive data
• I have considered security implications of my changes
• My changes do not introduce known vulnerabilities

🏗️ Contract-Specific (if applicable)

• Storage changes are backward compatible (or migration plan provided)
• Event emissions are appropriate and documented
• Error handling is comprehensive
• Gas/resource usage has been considered

💥 Breaking Changes

• This PR introduces breaking changes: No

📊 Performance Impact

• CPU/Memory: Negligible; new storage and events only when backup/DR used
• Gas costs: New endpoints (create_backup, verify_backup, record_recovery) cost gas on use
• Network: Indexer backup API adds minimal load

🔒 Security Considerations

• Risks: Backup manifests store integrity hash (not full data); recovery recording is permissioned (require_auth)
• Mitigations: All state-changing backup/DR actions require auth and are audit-logged

🚀 Deployment Notes

• Requires contract redeployment (new backup module and storage)
• Requires data migration
• Requires configuration changes
• No deployment changes needed

---