Cross-year clusters were appended after every event and loose letter, so a
band with a loose November letter plus February letters linked to another
year's event rendered the February ✉ card BELOW the November letter —
earlier-dated content sitting visually below later-dated content, breaking
the strict-time reading the band guarantees.
A cross-year cluster (no same-year EVENT anchor in this band) now emits its
card at the position of its earliest linked letter, in the band's
chronological order. Closes the spec gap pinned as REQ-015. Fixes review
finding #1.
Refs #850
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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