calendar: pull February's sanctoral calendar (pre-1955 pull, 2/12)

13 saints for February (12 real + the Vigil of St. Matthias), all
verified winning outright on a clean per-annum date — no secondary/
commemorated stubs needed this month, unlike January.

Two new scope exclusions found this month, beyond the usual octave/
temporal-continuation and fixed Lord/BVM feast ones: the generic
"Sanctae Mariae Sabbato" Saturday votive (not a real saint) and Feb 29's
leap-year redirect of the Vigil of St. Matthias (a real but not-yet-
modeled leap-day date shift).

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

src/data/calendar/saints/st-ignatius-of-antioch.yml

@@ -0,0 +1,11 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617), live kalendar
+# check (2029-02-01, no Sunday collision) -- winner outright, Duplex. No
+# unique Oratio/Antiphon in the source -- Common of a Martyr Bishop only.
+# (A different year, 2026, shows him transferred to Feb 3 instead when Feb 1
+# is a Sunday and Feb 2's Purification blocks the usual next-day slot -- the
+# transfer mechanism this app already models, not re-verified here.)
+id: st-ignatius-of-antioch
+name: "St. Ignatius of Antioch, Bishop and Martyr"
+rank: duplex
+common: common-of-a-martyr-bishop
+propers: null