Forge sensor: dispatch_retry_storm auto-bounce

feature_id: FEAT-FORGE-RELIABILITY

Detect: any Task in PLANNING_VALIDATED/IN_PROGRESS with more than 100 non_retriable_failure DispatchAudit rows in trailing 24h.
Heal (autonomy=auto): status BOUNCED, labels += auto-bounced/dispatch-retry-storm.
Seeded by 2026-07-24 POR-422 / POR-67 incident.