Description

Add parsec stack for managing dependent PR chains (stacked diffs).

Details

• parsec start <ticket> --on <parent-ticket> — create worktree based on parent ticket's branch
• parsec stack — show the dependency graph of active worktrees
• parsec stack sync — rebase the entire stack when base changes
• parsec ship with stacked PRs sets the correct base branch for each PR

Example

```bash
parsec start PROJ-1 --title "Add models"
parsec start PROJ-2 --on PROJ-1 --title "Add API endpoints"
parsec start PROJ-3 --on PROJ-2 --title "Add frontend"

parsec stack

PROJ-1 → PROJ-2 → PROJ-3

parsec ship PROJ-1 # PR to main
parsec ship PROJ-2 # PR to feature/PROJ-1
parsec ship PROJ-3 # PR to feature/PROJ-2
```

Implementation

• Add parent_ticket field to workspace metadata
• Track stack relationships in state.json
• Modify ship to use parent branch as PR base
• Add stack visualization command

Priority

High difficulty, high differentiation