grace-execute

<skill> <preflight> Require one active bundle with approved, identity-matched `spec.xml` and `plan.xml`. Approved plans are immutable. Read context, projections, assertions, scopes, task dependencies, and verification before editing. Reject phase-incompatible plans before writes: `MustPassCommand` must be leaf project evidence, and neither target assertions nor post-write task verification may invoke `--assertions current` or nest GRACE lifecycle commands. Supersede and replan instead of editing an approved conflict in place. </preflight> <assertion_commands> - Active-baseline preflight before observed writes: `grace lint --path PROJECT --assertions current` - Selected baseline: `grace lint --path PROJECT --change C-ID --assertions baseline` (add `--run-commands` when the baseline declares `MustPassCommand`) - Selected target without commands: `grace lint --path PROJECT --change C-ID --assertions target` - Selected target with command evidence: `grace lint --path PROJECT --change C-ID --assertions target --run-commands` - Final end-state validation: `grace lint --path PROJECT --change C-ID --assertions final` (add `--run-commands` when the target declares `MustPassCommand`) - Parallel preflight: `grace lint --path PROJECT --parallel-preflight` </assertion_commands> <mode_selection> Wait for explicit `sequential` or `parallel-safe` choice. Parallel-safe requires the explicit preflight to pass. Workers never mutate approved plans; durable `.grace` changes are applied centrall...