f0c1b38c5b
Introduce a compensating workflow that launches the dedicated AWX rollback template when a deployment cannot be started or fails midway. - add task states: rollback_pending, rolling_back, rolled_back, rollback_failed, rollback_acknowledged - add RollbackJob model to track the compensating AWX run separately from the deploy run, preserving both job IDs for audit - hold resource reservations in 'rollback' status until cleanup succeeds so a failed cleanup cannot be masked by a later delivery - poll rollback jobs with a 2-minute launch timeout; an unknown launch result surfaces as a recoverable failure instead of re-launching - protect finished/register_failed/rolled-back tasks from rollback; register_failed keeps the healthy instance and its resource usage - add DELIVERY_ROLLBACK_TEMPLATE_ID config; without it, failures are marked rollback_failed and require manual cleanup - use unique pending-<task_id> placeholder for executor job IDs