Normalize versicle notation to plain V./R. across propers

Unicode ℣/℟ (U+2123/U+211F) were mixed unpredictably with plain V./R.
across ~550 proper YAML files, sometimes within the same file. Screen
readers can't announce the unicode glyphs. Replace all instances with
plain text.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01QC6jHsj75xcsTkapqJR6fD

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

@@ -8,12 +8,12 @@ text:
     Orémus.
     Indulgéntiam nobis, quǽsumus, Dómine, beáta Doróthea Virgo et Martyr implóret: quæ tibi grata semper éxstitit, et mérito castitátis, et tuæ professióne virtútis.
     Per Dóminum nostrum Jesum Christum, Fílium tuum: qui tecum vivit et regnat in unitáte Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
-    ℟. Amen.
+    R. Amen.
   en: |
     Let us pray.
     O Lord, we pray thee, that thy blessed handmaiden and witness Dorothy in whom Thou hast ever been well pleased, because of her worthy maidenhood and her mighty showing-forth of thy power, may entreat thy pardon on our behalf.
     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.
+    R. Amen.
 status:
   la: verified
   en: verified