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/vespers-hymn-holy-name-of-jesus.yml

@@ -0,0 +1,61 @@
+# Read from web/www/horas/Latin/Tempora/Nat2-0.txt's own [Hymnus
+# Vespera] ("Jesu, dulcis memória") and its English counterpart -- the
+# first of the three-part "Jesu dulcis memoria" hymn cycle (see the
+# -matins- and -lauds- sibling files for the other two parts).
+id: vespers-hymn-holy-name-of-jesus
+text:
+  la: |
+    Jesu, dulcis memória,
+    Dans vera cordis gáudia:
+    Sed super mel, et ómnia,
+    Ejus dulcis præséntia.
+
+    Nil cánitur suávius,
+    Nil audítur jucúndius,
+    Nil cogitátur dúlcius,
+    Quam Jesus Dei Fílius.
+
+    Jesu, spes pœniténtibus,
+    Quam pius es peténtibus!
+    Quam bonus te quæréntibus!
+    Sed quid inveniéntibus?
+
+    Nec lingua valet dícere,
+    Nec líttera exprímere:
+    Expértus potest crédere,
+    Quid sit Jesum dilígere.
+
+    Sis, Jesu, nostrum gáudium,
+    Qui es futúrus prǽmium:
+    Sit nostra in te glória,
+    Per cuncta semper sǽcula.
+    Amen.
+  en: |
+    Jesu, the very thought of thee,
+    With sweetness fills my breast;
+    But sweeter far thy face to see,
+    And in thy presence rest.
+
+    Nor voice can sing, nor heart can frame,
+    Nor can the memory find,
+    A sweeter sound than thy blest Name,
+    O Saviour of mankind.
+
+    O hope of every contrite heart,
+    O joy of all the meek,
+    To those who fall, how kind thou art;
+    How good to those who seek.
+
+    But what to those who find? This truth
+    No tongue nor pen can show:
+    The love of Jesus, what it is,
+    None but his loved ones know.
+
+    Jesu, our only joy be thou,
+    As thou our prize wilt be;
+    Jesu, be thou our glory now,
+    And through eternity.
+    Amen.
+status:
+  la: verified
+  en: verified