Add 6 more April saints previously never added

St. Isidore of Seville, St. Vincent Ferrer, St. Hermenegild, St. Anselm,
St. Fidelis of Sigmaringen, St. Peter Canisius -- April complete.
St. Peter Canisius is the second common-of-a-confessor-doctor saint
(after St. John Damascene in March), same benedictusCommon reuse
pattern. St. Hugh, Abbot (Apr 1) checked and correctly skipped: his own
file is Commemoratio-rank with only a collect, no Lectio content at
all to source.

npm test (365 tests) and tsc --noEmit both pass.

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

src/data/propers/common/st-fidelis-of-sigmaringen-collect.yml

@@ -0,0 +1,26 @@
+# Read directly from web/www/horas/Latin/Sancti/04-24.txt's own
+# [Oratio] and its English counterpart.
+id: st-fidelis-of-sigmaringen-collect
+text:
+  la: |
+    Orémus.
+    Deus, qui beátum Fidélem, seráphico spíritus ardóre succénsum, in veræ fídei
+    propagatióne martýrii palma et gloriósis miráculis decoráre dignátus es: ejus,
+    quǽsumus, méritis et intercessióne, ita nos per grátiam tuam in fide et caritáte
+    confírma; ut in servítio tuo fidéles usque ad mortem inveníri mereámur.
+    Per Dóminum nostrum Jesum Christum, Fílium tuum: qui tecum vivit et regnat in unitáte
+    Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
+    ℟. Amen.
+  en: |
+    Let us pray.
+    God, Who didst vouchsafe to enkindle in blessed Fidelis the fire of thy Seraphim, and
+    to glorify his toil to give men a true knowledge of thee by the palm-branch of
+    martyrdom and by great signs and wonders, be entreated, we beseech thee, for his sake
+    and by his prayers, and so establish us in the knowledge and love of thee, that we
+    also, like him, may be found faithful even unto death in serving of thee.
+    Through Jesus Christ, thy Son our Lord, Who liveth and reigneth with thee, in the
+    unity of the Holy Ghost, God, world without end.
+    ℟. Amen.
+status:
+  la: verified
+  en: verified

src/data/propers/common/st-hermenegild-collect.yml

@@ -0,0 +1,22 @@
+# Read directly from web/www/horas/Latin/Sancti/04-13.txt's own
+# [Oratio] and its English counterpart.
+id: st-hermenegild-collect
+text:
+  la: |
+    Orémus.
+    Deus, qui beátum Hermenegíldum Mártyrem tuum cælésti regno terrénum postpónere
+    docuísti: da quǽsumus nobis; ejus exémplo cadúca despícere, atque ætérna sectári.
+    Per Dóminum nostrum Jesum Christum, Fílium tuum: qui tecum vivit et regnat in unitáte
+    Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
+    ℟. Amen.
+  en: |
+    Let us pray.
+    O God, Who didst teach thy blessed Martyr Hermenegild to choose an heavenly rather
+    than an earthly crown, grant, we beseech thee, that we, like him, may so pass through
+    things temporal that we finally miss not those which are eternal.
+    Through Jesus Christ, thy Son our Lord, Who liveth and reigneth with thee, in the
+    unity of the Holy Ghost, God, world without end.
+    ℟. Amen.
+status:
+  la: verified
+  en: verified

src/data/propers/common/st-peter-canisius-collect.yml

@@ -0,0 +1,23 @@
+# Read directly from web/www/horas/Latin/Sancti/04-27.txt's own
+# [Oratio] and its English counterpart.
+id: st-peter-canisius-collect
+text:
+  la: |
+    Orémus.
+    Deus, qui ad tuéndam cathólicam fidem beátum Petrum Confessórem tuum virtúte et
+    doctrína roborásti: concéde propítius; ut ejus exémplis et mónitis errántes ad
+    salútem resipíscant, et fidéles in veritátis confessióne persevérent.
+    Per Dóminum nostrum Jesum Christum, Fílium tuum: qui tecum vivit et regnat in unitáte
+    Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
+    ℟. Amen.
+  en: |
+    Let us pray.
+    O God, who didst give strength and learning to blessed Peter thy Confessor for the
+    defense of the Catholic faith, mercifully grant, that by his example and teaching,
+    the erring may be saved and the faithful remain constant in the confession of truth.
+    Through Jesus Christ, thy Son our Lord, Who liveth and reigneth with thee, in the
+    unity of the Holy Ghost, God, world without end.
+    ℟. Amen.
+status:
+  la: verified
+  en: verified

src/data/propers/common/st-vincent-ferrer-collect.yml

@@ -0,0 +1,24 @@
+# Read directly from web/www/horas/Latin/Sancti/04-05.txt's own
+# [Oratio] and its English counterpart.
+id: st-vincent-ferrer-collect
+text:
+  la: |
+    Orémus.
+    Deus, qui Ecclésiam tuam beáti Vincéntii Confessóris tui méritis et prædicatióne
+    illustráre dignátus es: concéde nobis fámulis tuis; ut et ipsíus instruámur exémplis
+    et ab ómnibus ejus patrocínio liberémur advérsis.
+    Per Dóminum nostrum Jesum Christum, Fílium tuum: qui tecum vivit et regnat in unitáte
+    Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
+    ℟. Amen.
+  en: |
+    Let us pray.
+    O God, Who wast pleased to enlighten thy Church through the worthy deeds and Gospel
+    preaching of thy blessed Confessor Vincent, grant unto us thy servants grace so to
+    order our lives after his example, that we, being helped by his protection, may by
+    thee be ever delivered from all evil.
+    Through Jesus Christ, thy Son our Lord, Who liveth and reigneth with thee, in the
+    unity of the Holy Ghost, God, world without end.
+    ℟. Amen.
+status:
+  la: verified
+  en: verified