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-apostle-collect.yml

@@ -6,12 +6,12 @@ text:
     Orémus.
     Ecclésiam tuam, Dómine, benígnus illústra: ut beáti Joánnis Apóstoli tui et Evangelístæ, illumináta doctrínis, ad dona pervéniat sempitérna.
     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.
     Shine upon thy Church, O Lord, in thy goodness, that, enlightened by the teachings of Blessed John, thy Apostle and Evangelist, she may attain to everlasting gifts.
     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