using-git-worktrees

# using-git-worktrees OPTIONAL. Per-task filesystem isolation for parallel agent work — opt-in only, never the default path. Routed to by `subagent-driven-development` and `dispatching-parallel-agents` when, and only when, the caller requests isolation. If no isolation is requested, this skill does not run; parallel units share the working tree under their own discipline. Isolation is convenience, not soul. It lets concurrent units edit files without collision. It changes nothing about the gates — the consolidated work still clears `commit-gate` and the single `finishing-a-development-branch` terminal step, run by the caller. What it MUST NOT do is multiply that terminal step into one PR per unit. ## Pre-flight Read these, or STOP and surface the gap — never guess: - `<project-root>/.codearbiter/CONTEXT.md` — confirm the repo is a git repo and the base/working branch. Confirm the caller passed an explicit isolation opt-in AND the parallel unit list (from `plans/<slug>.md`). Absent either, do not stand up worktrees. ## Phase 1 — Provision · gate: BLOCK Stand up one worktree per parallel unit. For each unit, create a worktree on a fresh branch off the current base, under a dedicated parent directory outside the main working tree (e.g. `../.codearbiter-worktrees/<slug>`): - One worktree, one branch, one unit. Never share a worktree across units. - Branch name MUST be unique and traceable to its unit's task ID. - Record each worktree path and branch in a dedicated manife...