Give the Matins ferial hymn its own text per weekday, not one for all

matins-hymn-ferial.yml turned out to already be Monday's own hymn
("Somno reféctis ártubus"), mislabeled as a single fixed year-round
text and used unconditionally for every weekday -- the source
(Psalterium/Special/Matutinum Special.txt) genuinely varies this hymn
Monday through Saturday, the classic "week of hymns". Caught first on
Friday ("Tu Trinitátis Únitas" expected, Monday's text shown), then
again on a real Ember Saturday ("Summæ Deus cleméntiæ" expected).

Authored matins-hymn-ferial-{tuesday,wednesday,thursday,friday,
saturday}.yml (Monastic 1617 text, live-verified against the CGI
instance directly, including Friday's own real M-track word-swaps) and
wired resolveMatinsHymn's final fallback tier to pick by day.weekday.
Sunday is left on the existing placeholder, documented as a real,
more complex not-yet-understood gap (a two-hymn source split).

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

src/data/propers/common/matins-hymn-ferial-thursday.yml

@@ -0,0 +1,83 @@
+# Thursday's own plain ferial Matins hymn (Psalterium/Special/Matutinum
+# Special.txt's "Day4 Hymnus" — Day0=Sunday .. Day6=Saturday, live-checked
+# 2026-09-04, 2026-09-03). Monastic 1617's own "Day4 HymnusM" is a bare
+# `@:Day4 Hymnus` cross-reference with no substitution — identical to the
+# secular text below.
+#
+# Closing doxology stanza intentionally omitted — shared across every
+# weekday via matins-hymn-doxology-per-annum.yml (see hours/matins.ts).
+id: matins-hymn-ferial-thursday
+text:
+  la: >-
+    Nox atra rerum cóntegit
+
+    Terræ colóres ómnium:
+
+    Nos confiténtes póscimus
+
+    Te, juste judex córdium.
+
+
+    Ut áuferas piácula,
+
+    Sordésque mentis ábluas:
+
+    Donésque, Christe, grátiam,
+
+    Ut arceántur crímina.
+
+
+    Mens ecce torpet ímpia,
+
+    Quam culpa mordet nóxia:
+
+    Obscúra gestit tóllere,
+
+    Et te, Redémptor, quǽrere.
+
+
+    Repélle tu calíginem
+
+    Intrínsecus quam máxime,
+
+    Ut in beáto gáudeat
+
+    Se collocári lúmine.
+  en: >-
+    The dusky veil of night hath laid
+
+    The varied hues of earth in shade;
+
+    Before Thee, righteous Judge of all,
+
+    We contrite in confession fall.
+
+
+    Take far away our load of sin,
+
+    Our soiled minds make clean within:
+
+    Thy sov'reign grace, O Christ, impart,
+
+    From all offence to guard our heart.
+
+
+    For lo! our mind is dull and cold,
+
+    Envenomed by sin's baneful hold:
+
+    Fain would it now the darkness flee,
+
+    And seek, Redeemer, unto Thee.
+
+
+    Far from it drive the shades of night,
+
+    Its inmost darkness put to flight;
+
+    Till in the daylight of the blest
+
+    It joys to find itself at rest.
+status:
+  la: verified
+  en: verified