Salvages #23772 by @thewillhuang. Adds 'review' as a valid kanban task
status and extends dispatch_once to monitor the review column as a
second dispatch source (in addition to the existing ready column).
- Adds 'review' to VALID_STATUSES
- Adds claim_review_task() — atomically transitions review → running
- Adds has_spawnable_review() — health telemetry mirror
- Extends dispatch_once with a review column dispatch loop
- Review agents get 'sdlc-review' skill auto-loaded
Resolved 2 conflicts (VALID_STATUSES merge with main's 'scheduled' state,
test file additions). Adapted claim_review_task to main's
ttl_seconds: Optional[int] = None convention (matches claim_task).
f55d94a1e0