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-gabriel-archangel-commemoration.yml

@@ -11,7 +11,7 @@ text:
     ipsíus patrocínium sentiámus in cælis.
     Qui vivis et regnas cum Deo Patre, in unitáte Spíritus Sancti, Deus, per ómnia sǽcula
     sæculórum.
-    ℟. Amen.
+    R. Amen.
   en: |
     Ant. The Angel Gabriel * appeared to Daniel and said: From the beginning of thy prayers the word came forth: and I am come to show it to thee, because thou art a man of desires: therefore do thou mark the word, and understand the vision.
     V. The Lord led the just through the right ways:
@@ -22,7 +22,7 @@ text:
     his feast upon earth may feel his protection in heaven.
     Who livest and reignest with God the Father, in the unity of the Holy Ghost, God, world
     without end.
-    ℟. Amen.
+    R. Amen.
 status:
   la: draft
   en: draft