Italian Year-Styles (More Veneto) (義大利紀年式)

THE ITALIAN YEAR-STYLES — the archivists' triple trap: for most of a millennium the great Italian cities could not agree what year it was, because they could not agree when it BEGAN. FLORENCE opened the year on 25 March (the Annunciation, ab Incarnatione — the very Lady Day style England kept, and the catalogue's oldStyle engine serves); VENICE on 1 March (the famous MORE VENETO, kept until the Republic fell in 1797); PISA on 25 March — but A YEAR AHEAD. THE PISA–FLORENCE LAW is the trap of traps, asserted at load: identical style-name, yet the calculus Pisanus ran exactly ONE year ahead of the stile fiorentino on EVERY day of EVERY year — two archives, one style, one guaranteed year of error; the first question a medievalist asks of a Tuscan charter is WHICH 25 March. THE M.V. CELL asserted: '10 February 1610 more veneto' = 10 February 1611 common. The Dante invariance (September dates agree everywhere but Pisa), the Lady Day echo to the oldStyle engine (Washington's 1731 reproduces as the Florentine year), and the styles' historical ends (Tuscany 1750, Venice 1797) all carried. Western becomes fifty-one. Pure compute, no LLM.

Cost: 1 TIAN Points per call. tRPC procedure italianStyles.year.