calendar: pull May's sanctoral calendar (pre-1955 pull, 5/12)

18 saints for May (16 real + 2 stubs). Both stubs this month are
genuinely unwinnable in the real historical calendar in any year (their
competing observances are fixed-date, not movable) — flagged explicitly
in their own files as distinct from the usual "just an artifact of the
year checked" caveat.

A second, distinct feast of St. Michael (his Apparition, May 8) is kept
as its own record separate from st-michael.yml's Sept 29 dedication
feast, same precedent as the two Chair-of-Peter feasts.

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

src/data/calendar/saints/ss-alexander-eventius-theodulus-and-juvenal.yml

@@ -0,0 +1,14 @@
+# Secondary commemoration on 05-03, pulled from Divinum Officium's kalendar
+# headline (Monastic Tridentinum 1617) -- loses the day to the Finding of
+# the Holy Cross (a fixed-date feast of the Lord, out of scope, see
+# sanctoral-calendar.yml), so unlike most other stubs in this set, this
+# isn't just an artifact of the specific year checked: their competing
+# observance is likewise fixed-date, meaning no year exists where they'd
+# win independently. That query doesn't expose a secondary entry's own
+# rank, only its name -- simplex here is an unverified placeholder, same
+# caveat as every other stub. No text pulled at all yet.
+id: ss-alexander-eventius-theodulus-and-juvenal
+name: "Ss. Alexander I, Eventius, and Theodulus, Martyrs, and Juvenal, Bishop and Confessor"
+rank: simplex
+common: common-of-several-martyrs
+propers: null