1. Peer percentile is now a tie-aware rank against the OTHER issuers
((worse + 0.5*tied)/(peers-1)): an all-equal group maps to 50 (not 100), the
median maps to 50, a unique best to 100, a unique worst to 0.
2. Deterministic reads use the consecutive non-null suffix ending at the latest
point (>=3 values): a null latest or an internal gap yields no read, so a read
never reflects a period displayed as n/a.
3. Peer filtering excludes non-finite (NaN/±inf) as well as null, including an
invalid subject.
Tests updated + added (all-equal, median rank, non-finite, latest-null history,
internal gap). 15 passed.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
dennisthiessenandClaude Opus 4.8
979b4047dc