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/ss-john-and-paul-collect.yml

@@ -7,12 +7,12 @@ text:
     Orémus.
     Quǽsumus, omnípotens Deus: ut nos gemináta lætítia hodiérnæ festivitátis excípiat, quæ de beatórum Joánnis et Pauli glorificatióne procédit; quos éadem fides et pássio vere fecit esse germános.
     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.
     Almighty God, fill us, we beseech thee, with the twofold gladness which doth flow down upon this bright day from the glory of thy blessed servants John and Paul, whom one faith and one suffering made to be brothers indeed.
     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