Complete Marian Saturday: proper Matins/Lauds hymns, ferial antiphons

Design (direct instruction): Marian Saturday is its own rank tier,
between simplex and vigil in vu's FeastClass scale -- beats a plain
Simplex saint (commemorated in return), loses cleanly with zero trace
to anything Vigil-or-higher. Deliberately not the full historical
Officium Sabbatorum B.M.V. ("no little office"): ferial psalmody is
kept everywhere, only the antiphons swap to Marian text; Matins and
Lauds each get a real proper Marian hymn; the Marian collect applies
whenever the day wins.

The calendar-side mechanism (calendar/index.ts's applyMarianSaturday)
and a collect/Benedictus antiphon already existed from an earlier
session -- authored what was still missing: matins-hymn-marian-
saturday.yml (Matins had nothing at all) and lauds-{capitulum,
responsory,hymn,versicle}-marian-saturday.yml.

Also found and fixed 3 real bugs from that earlier, unverified pass:
Lauds' own hymn ("O gloriósa Dómina") was sitting under the plain
ferial lauds-hymn-saturday id instead of its own marian-saturday id;
that id's capitulum/responsory/versicle siblings were live-verified
from a different, privileged Lenten Ember Saturday, not a genuine
per-annum ferial Saturday -- corrected to the real content ("Auróra
jam spargit polum" / Rom 13:12-13 / "Sana ánimam meam" / "Repléti
sumus mane misericórdia tua", live-verified against a clean September
Ember Saturday); and the Lauds psalmody override used the real
historical proper psalm set (92/99/62) instead of the ferial one,
rolled back per direct instruction to plain ferial psalms (50, 142,
the split Canticle of Moses) with only the antiphons swapped.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AGjUyhUZJaSjiniEmnLdak

src/data/propers/common/lauds-responsory-marian-saturday.yml

@@ -0,0 +1,23 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617), Lauds
+# live query, 2026-10-03 (a plain Sanctæ Mariæ Sabbato ~ Simplex day).
+# Identical text to lauds-responsory-nativity-bvm.yml — the same Common-
+# of-the-BVM responsory reused by both, not a coincidence.
+id: lauds-responsory-marian-saturday
+text:
+  la: |
+    R.br. Ave María, grátia plena, * Dóminus tecum.
+    R. Ave María, grátia plena, * Dóminus tecum.
+    V. Benedícta tu in muliéribus, et benedíctus fructus ventris tui
+    R. Dóminus tecum.
+    V. Glória Patri, et Fílio, * et Spirítui Sancto.
+    R. Ave María, grátia plena, * Dóminus tecum.
+  en: |
+    R.br. Hail Mary full of grace, * the Lord is with thee.
+    R. Hail Mary full of grace, * the Lord is with thee.
+    V. Benedícta tu in muliéribus, et benedíctus fructus ventris tui
+    R. The Lord is with thee.
+    V. Glory be to the Father, and to the Son, * and to the Holy Ghost.
+    R. Hail Mary full of grace, * the Lord is with thee.
+status:
+  la: verified
+  en: verified