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-john-baptist-de-la-salle-collect.yml

@@ -11,7 +11,7 @@ text:
     fíeri valeámus.
     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 God, who didst raise up the Confessor, St. John Baptist, to promote the Christian
@@ -21,7 +21,7 @@ text:
     salvation of souls, and may share his crown in heaven.
     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