Adds a 'Library Validation' card to the Settings page that wraps the
backend sweep API: trigger button, last-run timestamp, scanned/suspect
counts, by-format breakdown, and an expandable suspect-paths table.
Polls every 10s for up to 5 minutes after a scan is queued so the
report shows up without manual refreshing.
Also adds a download.validate_files switch to the Download Settings
section so the live per-file validation can be toggled from the UI
instead of via direct DB edits.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
bvandeusen
b43c35483f