Release v1.44.0

feat: add scud ralph command for sequential task execution

Ralph mode processes tasks one at a time with fresh agent context per
iteration, implementing the Ralph methodology:
- Fresh context each iteration (new tmux window per task)
- One task per loop with full completion before moving on
- Backpressure validation between tasks
- Automatic repair loop on validation failure

Key features:
- Uses existing SpawnSession for TUI monitoring integration
- Respects task dependencies from DAG
- Configurable max iterations, repair attempts
- Supports --dry-run to preview execution plan
- Optional git push after each successful task

Essentially "swarm with round_size=1" - simple sequential execution
using the same infrastructure.