propers: add February's collect and antiphon text

Real collect text for the 6 February saints that have one, plus a real
antiphon for the 2 that have one of their own — same extraction method
as January (fully-rendered live-engine output, not the raw source files'
own shorthand endings).

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

src/data/propers/common/st-dorothea-collect.yml

@@ -0,0 +1,19 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617) — read
+# directly from the reference engine's own real-date output (2029-02-06, a
+# year that date doesn't collide with a Sunday). Same convention as
+# data/propers/temporal/*-collect.yml.
+id: st-dorothea-collect
+text:
+  la: |
+    Orémus.
+    Indulgéntiam nobis, quǽsumus, Dómine, beáta Doróthea Virgo et Martyr implóret: quæ tibi grata semper éxstitit, et mérito castitátis, et tuæ professióne virtútis.
+    Per Dóminum nostrum Jesum Christum, Fílium tuum: qui tecum vivit et regnat in unitáte Spíritus Sancti, Deus, per ómnia sǽcula sæculórum.
+    ℟. Amen.
+  en: |
+    Let us pray.
+    O Lord, we pray thee, that thy blessed handmaiden and witness Dorothy in whom Thou hast ever been well pleased, because of her worthy maidenhood and her mighty showing-forth of thy power, may entreat thy pardon on our behalf.
+    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.
+status:
+  la: verified
+  en: verified