cadastre_jobs.phase_state is shared between ALL parallel Celery workers
of the same job. The early-exit triggered as soon as the FIRST worker
wrote phase=done via progress_cb — all subsequent workers (reading same
shared row) bailed without work.
Effect: pilot v7 made 5 NSPD requests for 50 quarters (=0.1/quarter).
Full ekb_full job #8: 4950 req / 2408 quarters = 2/quarter — 95% workers
early-exited without doing snapshot phase.
Root cause of 1.6% parcels coverage. Fix A/B/C only partially helped
because most workers never reached Phase 1/1.5.
Solution: delete the early-exit. Idempotency is guaranteed by
ON CONFLICT DO UPDATE in every upsert_* — re-enqueued tasks
write same rows without duplicates.
Closes part of #168 (root-cause fix for race condition revealed by #182 metrics).
