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/chair-of-st-peter-at-rome-commemoration.yml

@@ -14,7 +14,7 @@ text:
     Orémus.
     Deus, qui beáto Petro Apóstolo tuo, collátis clávibus regni cæléstis, ligándi atque solvéndi pontifícium tradidísti: concéde; ut, intercessiónis ejus auxílio, a peccatórum nostrórum néxibus liberémur:
     Qui vivis et regnas cum Deo Patre, in unitáte Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
-    ℟. Amen.
+    R. Amen.
   en: |
     Ant. Thus saith the Lord unto Simon Peter: Whatsoever thou shalt bind on earth, shall be bound in heaven; and whatsoever thou shalt loose on earth, shall be loosed in heaven.
     V. They have declared the works of God:
@@ -22,7 +22,7 @@ text:
     Let us pray.
     O God, Who hast given unto thy Blessed Apostle Peter the keys of the kingdom of heaven, and the power to bind and to loose, loose us, we beseech thee, at his mighty intercession, from all the bands of our sins.
     Who livest and reignest with God the Father in the unity of the Holy Spirit, God, world without end.
-    ℟. Amen.
+    R. Amen.
 status:
   la: draft
   en: draft