propers: add November's collect and antiphon text

9 collects, 3 antiphons -- including backfilling the pre-existing All
Saints entry. Also updates two pre-existing tests whose shared date
(2025-11-30, Advent I Sunday) now correctly shows St. Andrew commemorated
alongside it, confirmed against the live reference engine.

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

src/data/propers/common/st-silvester-abbot-collect.yml

@@ -0,0 +1,17 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617) — read
+# directly from the reference engine's own real-date output (2032-11-26).
+id: st-silvester-abbot-collect
+text:
+  la: |
+    Orémus.
+    Clementíssime Deus, qui sanctum Silvéstrum Abbátem, sǽculi hujus vanitátem in apérto túmulo pie meditántem, ad erémum vocáre, et præcláris vitæ méritis decoráre dignátus es: te súpplices exorámus; ut, ejus exémplo terréna despiciéntes, tui consórtio perfruámur ætérno.
+    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.
+    Most merciful God, Who when the holy Abbot Sylvester was devoutly meditating upon the vanity of this world beside an open grave, graciously willed to call him into the desert and enrich him with unusual merits, we humbly pray that, following his example, despising the things of earth, we may thoroughly enjoy Thy everlasting presence.
+    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