calendar: pull October's sanctoral calendar (pre-1955 pull, 10/12)

16 saints (14 real winners + 2 stubs). Three monastic-calendar-specific
finds this month: Ss. Placid and Companions (Oct 5, St. Benedict's own
disciple, Duplex II. classis -- absent from the base Tridentine table
entirely), St. Justina (Oct 7, reassigns what the base table gives to
St. Marcus, Pope), and St. Gall (Oct 16, founder of St. Gallen, also
absent from the base table). No octave-gap exclusions this month.

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

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

@@ -0,0 +1,14 @@
+# A monastic-calendar-specific addition: absent from the base Tridentine
+# table (1570.txt) entirely, added by the monastic-specific delta table
+# (M1617.txt) -- fittingly, St. Gall (founder of the abbey of St. Gallen)
+# is one of the most distinctly monastic saints in this whole pull.
+# Verified live (Monastic Tridentinum 1617, 2025-10-16) -- winner
+# outright, Duplex, alone. No unique collect: the raw file at this MM-DD
+# slot (Sancti/10-16.txt) is actually St. Hedwig's (a later addition to
+# this filename slot) -- a live prayTertia query for the Monastic 1617
+# track returns no Oratio at all, confirming propers: null is correct.
+id: st-gall
+name: "St. Gall, Abbot"
+rank: duplex
+common: common-of-an-abbot
+propers: null