[plan] Improve concurrency implementation with conc library enhancements

[github-actions]

Overview

This tracking issue implements improvements to gh-aw's usage of the sourcegraph/conc library for concurrent artifact downloading, based on findings from the Go Fan review.

Source: Discussion #8587

Current State

The project currently uses conc for concurrent artifact downloading in pkg/cli/logs_orchestrator.go with:

• ✅ Scoped concurrency with pool.NewWithResults[DownloadResult]()
• ✅ Bounded concurrency via WithMaxGoroutines(MaxConcurrentDownloads)
• ✅ Automatic panic recovery
• ✅ Type-safe result collection

Planned Improvements

High Priority

1. Add context cancellation support - Enable graceful shutdown on Ctrl+C for long-running downloads
2. Document concurrency decisions - Explain configuration choices and behavior guarantees

Medium Priority

3. Add concurrent download test coverage - Test panic recovery, result ordering, and resource cleanup
4. Document panic behavior - Clarify automatic panic recovery for code reviewers

Lower Priority

5. Make concurrency limits configurable - Allow tuning based on system resources and API limits

Benefits

• 🎯 Better user experience: Graceful cancellation of long-running operations
• 📚 Improved maintainability: Clear documentation of concurrency decisions
• 🛡️ Regression prevention: Comprehensive test coverage for concurrent behavior
• ⚙️ Flexibility: Configurable concurrency based on environment

Related Resources

• sourcegraph/conc GitHub
• Current usage: pkg/cli/logs_orchestrator.go:481
• Module summary: specs/mods/sourcegraph-conc.md

AI generated by Plan Command for discussion #8587