Improve GCS Workqueue Test Coverage

[aryasoni98]

Problem

The GCS workqueue package has only 1.1% test coverage and needs comprehensive testing.

Current State

• ❌ workqueue/gcs package: 1.1% test coverage
• Limited tests for queue operations
• No tests for in-progress key management
• No tests for dead letter queue functionality
• No tests for lease management
• No tests for error handling scenarios

Acceptance Criteria

• Queue operations tested
• In-progress key management tested
• Dead letter queue functionality tested
• Lease management tested
• Error handling scenarios tested
• Test coverage >80%

Tasks

Queue Operations Testing

• Test queue creation and initialization
• Test adding items to queue
• Test removing items from queue
• Test queue enumeration
• Test queue state management

In-Progress Key Management Testing

• Test starting work on keys
• Test completing work on keys
• Test requeuing keys
• Test key state transitions
• Test concurrent key processing

Dead Letter Queue Testing

• Test moving keys to dead letter queue
• Test dead letter queue enumeration
• Test dead letter queue cleanup
• Test dead letter queue metadata

Lease Management Testing

• Test lease creation and renewal
• Test lease expiration handling
• Test orphaned key detection
• Test lease conflict resolution

Error Handling Testing

• Test GCS connection errors
• Test permission errors
• Test network errors
• Test quota errors
• Test retry mechanisms

Integration Testing

• Test with real GCS bucket (if available)
• Test with mock GCS client
• Test concurrency scenarios
• Test performance under load

Test Files to Create/Update

• pkg/workqueue/gcs/gcs_test.go
• pkg/workqueue/gcs/mock_test.go

Success Metrics

• Target: >80% test coverage
• Current: 1.1%
• Measurement: go test -coverprofile=coverage.out ./pkg/workqueue/gcs/...