Survey of every mechanism that can block a job from dispatch across the
scheduler (election → allocation → commit): 18 blocking points in 6
categories. Only 3 produce a PEND reason (MATCH_FAIL + 2×NO_RESOURCE);
the limit plugin (4 configured limits), queue state, dispatch_window and
fairshare are configured but silent; 8 LSF-standard reason categories
(dependency/license/reservation/exclusive/worker-state/...) are missing or
stubbed. Includes a layered reason taxonomy and wiring priorities.
Co-Authored-By: Claude <noreply@anthropic.com>
