calendar: pull January's sanctoral calendar (pre-1955 pull, 1/12)

20 saints for January, verified per-day against Divinum Officium (Monastic
Tridentinum 1617): 13 that actually win their day outright (rank pulled
from a live per-date query, since the static 1570/M1617 calendar text
files turned out unreliable once monastic-specific overrides apply) and
7 stubs for saints that only ever get commemorated, with an explicitly
flagged, unverified simplex rank guess pending correction.

Deliberately out of scope: pure octave-continuation days (In Octava S.
Stephani, the Epiphany-octave ferias) and fixed-date feasts of the
Lord/BMV (Circumcision, Epiphany) — sanctoral only, not temporal.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/data/calendar/saints/st-anthony-abbot.yml

@@ -0,0 +1,12 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617,
+# web/www/horas/Latin/Sancti/01-17.txt's untagged/default [Rank] block --
+# Duplex;;3 -- ignoring its own "(sed rubrica cisterciensis)" alternate, same
+# convention as every other saint file in this set). No unique Oratio/Antiphon
+# in the source -- Common of an Abbot only. This is the same St. Anthony whose
+# real occurrence-engine behavior was used earlier to calibrate the Duplex-vs-
+# ordinary-Sunday precedence rule (calendar/commemorations.ts).
+id: st-anthony-abbot
+name: "St. Anthony, Abbot"
+rank: duplex
+common: common-of-an-abbot
+propers: null