propers: add June's collect and antiphon text

Real collect text for all 16 June saints that have one, plus a real
antiphon for 4 of them and a fifth (Ss. Peter and Paul) that deliberately
reuses the Chair-of-Peter-at-Antioch antiphon text, matching the source's
own cross-reference — same extraction method as prior months.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/data/propers/common/ss-peter-and-paul-antiphon.yml

@@ -0,0 +1,13 @@
+# Verified against Divinum Officium (Latin/English Sancti/06-29.txt's own
+# [Ant 1] — a deliberate cross-reference to Sancti/02-22 (the Chair of St.
+# Peter at Antioch's own antiphon), same text reused for the same reason:
+# both are about St. Peter's own office. Duplicated here, not shared,
+# matching this project's one-file-per-id convention (see
+# chair-of-st-peter-at-rome-antiphon.yml's own note on the same pattern).
+id: ss-peter-and-paul-antiphon
+text:
+  la: "Tu es pastor óvium, * Princeps Apostolórum, tibi tráditæ sunt claves regni cælórum."
+  en: "Thou art the Shepherd * of the sheep, and the Prince of the Apostles, and unto thee are given the keys of the kingdom of heaven."
+status:
+  la: verified
+  en: verified