The owner's page (issue #102) shows each Reader's Sighting record and offers
one action to wipe it. The counters ship before the Sighting feature that
moves them (issue #103) on purpose: the remedy for a false mark must exist
before marks can be made, or the first broken adapter is fixed with SQL
against production.
- 0010 adds sighting_agreements / sighting_disagreements, both zero-defaulted,
so every existing Reader reads as trusted.
- ReaderSummary carries both, plus Blocked() against SightingDisagreementLimit,
so the page states the verdict rather than making the owner derive it.
- ClearReaderMarks zeroes one Reader's pair.
