Add Our Lady of Guadalupe (Dec 12)

Sourced from the reference engine's national-calendar file. Own proper
collect, Ant 1, and Matins Nocturn 2 narrative reading (Juan Diego's
apparition account), same scope as the Our Lady of Lourdes feast --
Common of the BVM (C11) carries the rest. No canonization-deflation
question here (an apparition title, cultus confirmed 1754/1910). At
Duplex she ties the Immaculate Conception octave's threshold on a
non-closing day, which favors the occurring saint, so she wins Dec 12
outright.

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

src/data/calendar/saints/our-lady-of-guadalupe.yml

@@ -0,0 +1,15 @@
+# Read directly from the reference engine: Sancti/12-12n.txt --
+# "Beatæ Mariæ Virginis de Guadalupe;;Duplex;;3;;vide C11" (Common of
+# the BVM), the same rank family and `n` (national-calendar) sourcing as
+# apparition-of-the-immaculate-bvm.yml (Our Lady of Lourdes, Feb 11) --
+# not a canonization so the late-canonization deflation rule doesn't
+# apply; the cultus itself is old enough for the project's period
+# (Benedict XIV confirmed it 1754, Pius X named her Patroness of Latin
+# America). Own proper Oratio and [Ant 1], same scope as the Lourdes
+# feast -- no separate Vespers/Lauds antiphon set transcribed, Common of
+# the BVM (C11) carries the rest when she wins outright.
+id: our-lady-of-guadalupe
+name: "Our Lady of Guadalupe"
+rank: duplex
+common: common-of-the-bvm
+propers: "our-lady-of-guadalupe"