Quickstart: Close #2160 Coord-Shadows Read/Gate Arm
Validation scenarios (all through production paths):
1. Gate closes on every path — on a coord-topology mission with unchecked subtask rows, spec-kitty agent status --to for_review WITHOUT --subtasks-complete (and the orchestrator-api transition) is BLOCKED. See tests/specify_cli/status/test_infer_subtasks_primary.py and tests/specify_cli/orchestrator_api/test_transition_subtask_gate.py. 2. One subtask-row definition — guard, dashboard count, and rollback-uncheck agree on the bite battery (incl. re-appearing ## WPnn heading). See tests/specify_cli/core/test_subtask_rows.py. 3. Lane recovery leaks no status — a recovered coord-topology lane registers sparse-checkout and materializes no status.events.jsonl/status.json. See tests/specify_cli/lanes/test_worktree_allocator_recovery.py. 4. Live claim not stale — is_process_alive suppresses the stale flag for a live claim. See tests/specify_cli/core/test_process_liveness.py. 5. Progress tick keeps analysis fresh — checkbox flips don't change the freshness hash. See tests/specify_cli/cli/commands/agent/test_freshness_checkbox_insensitive.py.