feat: v2.0 Sprint 3 - Multipart Upload, Testing & Documentation (Part 2)

Sprint 3 Complete - Cloud Storage Full Implementation:

New Features:
✅ Multipart upload for large files (>100MB)
✅ Automatic part size (10MB) and concurrency (10 parts)
✅ MinIO testing infrastructure
✅ Comprehensive integration test script
✅ Complete cloud storage documentation

New Files:
- CLOUD.md - Complete cloud storage guide (580+ lines)
- docker-compose.minio.yml - MinIO + PostgreSQL + MySQL test setup
- scripts/test_cloud_storage.sh - Full integration test suite

Multipart Upload:
- Automatic for files >100MB
- 10MB part size for optimal performance
- 10 concurrent parts for faster uploads
- Progress tracking for multipart transfers
- AWS S3 Upload Manager integration

Testing Infrastructure:
- docker-compose.minio.yml:
  * MinIO S3-compatible storage
  * PostgreSQL 16 test database
  * MySQL 8.0 test database
  * Automatic bucket creation
  * Health checks for all services

- test_cloud_storage.sh (14 test scenarios):
  1. Service startup and health checks
  2. Test database creation with sample data
  3. Local backup creation
  4. Cloud upload to MinIO
  5. Cloud list verification
  6. Backup with cloud URI
  7. Database drop for restore test
  8. Restore from cloud URI
  9. Data verification after restore
  10. Cloud backup integrity verification
  11. Cleanup dry-run test
  12. Multiple backups creation
  13. Actual cleanup test
  14. Large file multipart upload (>100MB)

Documentation (CLOUD.md):
- Quick start guide
- URI syntax documentation
- Configuration methods (4 approaches)
- All cloud commands with examples
- Provider-specific setup (AWS S3, MinIO, B2, GCS)
- Multipart upload details
- Progress tracking
- Metadata synchronization
- Best practices (security, performance, reliability)
- Troubleshooting guide
- Real-world examples
- FAQ section

Sprint 3 COMPLETE!
Total implementation: 100% of requirements met

Cloud storage features now at 100%:
✅ URI parser and support
✅ Backup/restore/verify/cleanup integration
✅ Multipart uploads
✅ Testing infrastructure
✅ Comprehensive documentation

go.mod

@@ -20,9 +20,10 @@ require (
 	filippo.io/edwards25519 v1.1.0 // indirect
 	github.com/aws/aws-sdk-go-v2 v1.40.0 // indirect
 	github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.7.3 // indirect
-	github.com/aws/aws-sdk-go-v2/config v1.32.1 // indirect
-	github.com/aws/aws-sdk-go-v2/credentials v1.19.1 // indirect
+	github.com/aws/aws-sdk-go-v2/config v1.32.2 // indirect
+	github.com/aws/aws-sdk-go-v2/credentials v1.19.2 // indirect
 	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.18.14 // indirect
+	github.com/aws/aws-sdk-go-v2/feature/s3/manager v1.20.12 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/configsources v1.4.14 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.7.14 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/ini v1.8.4 // indirect
@@ -31,11 +32,11 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/internal/checksum v1.9.5 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.13.14 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/s3shared v1.19.14 // indirect
-	github.com/aws/aws-sdk-go-v2/service/s3 v1.92.0 // indirect
-	github.com/aws/aws-sdk-go-v2/service/signin v1.0.1 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sso v1.30.4 // indirect
-	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.9 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sts v1.41.1 // indirect
+	github.com/aws/aws-sdk-go-v2/service/s3 v1.92.1 // indirect
+	github.com/aws/aws-sdk-go-v2/service/signin v1.0.2 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sso v1.30.5 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.35.10 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sts v1.41.2 // indirect
 	github.com/aws/smithy-go v1.23.2 // indirect
 	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
 	github.com/charmbracelet/colorprofile v0.2.3-0.20250311203215-f60798e515dc // indirect