POST /prompt_manager/system/health runs the health check off-loop as a
read registry job of kind "health" (one at a time, beside a scan, not
cancellable, no file outcomes) and keeps the last report; GET returns it
or null. The check reads one snapshot on its own mode=ro connection,
closed in finally: integrity_check(100), foreign_key_check, stored hashes
against utils.hashing, duplicate pair rows, the legacy consistency
queries (now shared with check_consistency), and image links whose file
is gone, counted only under readable sources. An unavailable source, or
the absent Needs-review queue, makes its check unavailable and the
report incomplete instead of producing a count.
GET /prompt_manager/system/overview returns Library-eligible positive
prompts and active negative variants, indexed images, the last health
summary or null, backup null, the Needs-review count null, the effective
sources with whether they were auto-detected, and the thumbnail plan's
missing count. GET /prompt_manager/system/statistics lists runs and
average rating per category of Library parents, with the /stats totals.