worktree-isolation

WellForge parallel-safety discipline — what a git worktree isolates, what it does NOT, and the preflight before dispatching a parallel batch. Use whenever ≥2 dependency-independent agents are about to be dispatched ($wf-implement Step 3, $wf-orchestrate implementation stages), whenever an agent in a worktree hits a failure it cannot explain, and whenever deciding if a batch is safe to parallelize at all. Authoritative for the touches-nothing-outside-itself rule, the shared-state enumeration and its three dispositions, the env carry-in step, file-overlap DAG edges, and the isolate → constrain → integrate → reconcile → prune protocol.