Add nameLa mechanism for bilingual header, proof set of 11 feasts + St. Lawrence

Threads an optional nameLa field through SanctoralIdentity/SaintRecord/
TemporalFeastRecord/ActiveOctave so day-label.ts can render real Latin
proper names instead of always falling back to English. Authors the
proof set: all 11 named temporal feasts plus St. Lawrence (chosen to
exercise the octave-headline and octave-commemoration code paths too).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EwsZQMjALCvy7u9tFDWmuQ

src/data/calendar/saints/st-lawrence.yml

@@ -6,6 +6,10 @@
 # antiphon.
 id: st-lawrence
 name: "St. Lawrence, Martyr"
+# Standard Latin form, matching this app's own "St. X, Rank" naming
+# convention (the source's own martyrology/kalendar entries for him use
+# the genitive "S. Laurentii Martyris", dependent on an implied "Festum").
+nameLa: "Sanctus Laurentius, Martyr"
 rank: duplex-2-classis
 common: common-of-a-martyr
 propers: "st-lawrence"