propers: add September's collect and antiphon text

6 collects, 1 antiphon -- including backfilling the pre-existing Nativity
of the BVM entry now that the pulling methodology exists.

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

tests/calendar/september-sanctoral.test.ts

@@ -0,0 +1,78 @@
+import { describe, expect, it } from 'vitest';
+import { resolveDay } from '../../src/calendar';
+import { getDayCollect } from '../../src/hours/resolve-common';
+
+// Clean per-annum years for these dates (no Sunday collision) — see
+// data/calendar/saints/*.yml for per-saint source detail.
+describe('September sanctoral pull (first pass)', () => {
+  it('St. Giles wins outright at Simplex over a genuinely unwinnable stub', () => {
+    const day = resolveDay('2025-09-01');
+    expect(day.winner).toEqual({ kind: 'sanctoral', id: 'st-giles', name: 'St. Giles, Abbot', rank: 'simplex' });
+    expect(day.commemorations).toEqual([
+      { kind: 'sanctoral', id: 'ss-twelve-brothers', name: 'Ss. Twelve Brothers, Martyrs', rank: 'simplex' },
+    ]);
+  });
+
+  it('the Nativity of the BVM wins outright with a real proper collect and antiphon, commemorating a real secondary saint blocked by its own day (not its octave)', () => {
+    const day = resolveDay('2025-09-08');
+    expect(day.winner).toEqual({
+      kind: 'sanctoral',
+      id: 'nativity-bvm',
+      name: 'The Nativity of the Blessed Virgin Mary',
+      rank: 'duplex-2-classis',
+    });
+    expect(day.commemorations).toEqual([
+      { kind: 'sanctoral', id: 'st-hadrian', name: 'St. Hadrian, Martyr', rank: 'simplex' },
+    ]);
+    expect(getDayCollect(day).status.en).toBe('verified');
+  });
+
+  it("dates within the Nativity's own octave are excluded entirely, even where the source names a real secondary saint, pending octave support", () => {
+    const gorgoniusDay = resolveDay('2025-09-09');
+    expect(gorgoniusDay.winner.kind).toBe('temporal');
+    expect(gorgoniusDay.commemorations).toEqual([]);
+    const nicomedesDay = resolveDay('2025-09-15');
+    expect(nicomedesDay.winner.kind).toBe('temporal');
+    expect(nicomedesDay.commemorations).toEqual([]);
+  });
+
+  it('a monastic-calendar-specific reassignment replaces what the base Tridentine table treats as a plain Nativity-octave continuation', () => {
+    const day = resolveDay('2025-09-10');
+    expect(day.winner).toEqual({
+      kind: 'sanctoral',
+      id: 'st-nicholas-of-tolentino',
+      name: 'St. Nicholas of Tolentino, Confessor',
+      rank: 'semiduplex',
+    });
+  });
+
+  it('St. Matthew wins outright at Duplex II. classis with a real proper collect, distinct from his own Vigil the day before', () => {
+    const vigil = resolveDay('2029-09-20');
+    const day = resolveDay('2029-09-21');
+    expect(vigil.winner).toEqual({
+      kind: 'sanctoral',
+      id: 'vigil-of-st-matthew',
+      name: 'Vigil of St. Matthew',
+      rank: 'vigil',
+    });
+    expect(day.winner).toEqual({
+      kind: 'sanctoral',
+      id: 'st-matthew',
+      name: 'St. Matthew, Apostle and Evangelist',
+      rank: 'duplex-2-classis',
+    });
+    expect(getDayCollect(day).status.en).toBe('verified');
+  });
+
+  it('St. Jerome wins outright at Duplex with a real proper collect, alone', () => {
+    const day = resolveDay('2025-09-30');
+    expect(day.winner).toEqual({
+      kind: 'sanctoral',
+      id: 'st-jerome',
+      name: 'St. Jerome, Priest, Confessor and Doctor of the Church',
+      rank: 'duplex',
+    });
+    expect(day.commemorations).toEqual([]);
+    expect(getDayCollect(day).status.en).toBe('verified');
+  });
+});