- Add graceful shutdown handler that marks running features as 'interrupted'
before server exit (SIGTERM/SIGINT)
- Add 30-second shutdown timeout to prevent hanging on exit
- Add orphan detection to identify features with missing branches
- Add isFeatureRunning() for idempotent resume checks
- Improve resumeInterruptedFeatures() to handle features without saved context
- Add 'interrupted' status to FeatureStatusWithPipeline type
- Replace console.log with proper logger in auto-mode-service
- Add comprehensive unit tests for all new functionality (15 new tests)
Fixes#696🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>