Add the Most Holy Name of Jesus (Jan 2) as a proper temporal feast

Historically a floating Sunday (Jan 2-5, fixed to Jan 2 when no Sunday
falls there); per direct instruction this is instead fixed to Jan 2
every year for simplicity. Adds the feast's collect, Magnificat/
Benedictus antiphons, full Lauds psalmody, capitulum, the three-part
"Jesu dulcis memoria" hymn cycle (Vespers/Matins/Lauds), the Invitatory
antiphon, versicles, and two Matins nocturn readings (both St. Bernard
of Clairvaux), sourced from Tempora/Nat2-0.txt. Reuses the `fixed-date`
anchor kind added in the prior commit.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_014axryJBrRswYh2niA7WCUc

src/data/propers/common/matins-hymn-holy-name-of-jesus.yml

@@ -0,0 +1,62 @@
+# Read from web/www/horas/Latin/Tempora/Nat2-0.txt's own [Hymnus
+# Matutinum] ("Jesu, Rex admirábilis") and its English counterpart -- the
+# second of the three-part "Jesu dulcis memoria" hymn cycle traditionally
+# divided across Vespers/Matins/Lauds of this feast (see the -vespers- and
+# -lauds- sibling files for the other two parts).
+id: matins-hymn-holy-name-of-jesus
+text:
+  la: |
+    Jesu, Rex admirábilis,
+    Et triumphátor nóbilis,
+    Dulcédo ineffábilis,
+    Totus desiderábilis.
+
+    Quando cor nostrum vísitas,
+    Tunc lucet ei véritas,
+    Mundi viléscit vánitas,
+    Et intus fervet cáritas.
+
+    Jesu, dulcédo córdium,
+    Fons vivus, lumen méntium,
+    Excédens omne gáudium,
+    Et omne desidérium.
+
+    Jesum omnes agnóscite,
+    Amórem ejus póscite:
+    Jesum ardénter quǽrite,
+    Quæréndo inardéscite.
+
+    Te nostra, Jesu, vox sonet,
+    Nostri te mores éxprimant,
+    Te corda nostra díligant,
+    Et nunc, et in perpétuum.
+    Amen.
+  en: |
+    O Jesu, King most wonderful,
+    Thou conqueror renowned,
+    Thou sweetness most ineffable,
+    In whom all joys are found!
+
+    When once thou visitest the heart,
+    Then truth begins to shine;
+    Then earthly vanities depart;
+    Then kindles love divine.
+
+    O Jesu, light of all below,
+    Thou fount of life and fire,
+    Surpassing all the joys we know,
+    And all we can desire:
+
+    May every heart confess thy Name,
+    And ever thee adore;
+    And, seeking thee, itself inflame
+    To seek thee more and more.
+
+    Thee may our tongues forever bless;
+    Thee may we love alone;
+    And ever in our lives express
+    The image of thine own.
+    Amen.
+status:
+  la: verified
+  en: verified