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-cecilia-collect.yml

@@ -6,12 +6,12 @@ text:
     Orémus.
     Deus, qui nos ánnua beátæ Cæcíliæ Vírginis et Mártyris tuæ solemnitáte lætíficas: da, ut, quam venerámur offício, étiam piæ conversatiónis sequámur exémplo.
     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 year by year dost gladden thy people by the solemn feast of thy blessed Virgin and Martyr Cecilia, grant unto us, we beseech thee, not only devoutly to observe the same, but also to follow after the pattern of her godly conversation.
     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