Extend closing Gloria Patri to canticles, centralize instead of baking it in

Benedictus, Magnificat, and Nunc Dimittis had the Gloria Patri baked
verbatim into their propers YAML with no Triduum suppression; Matins'
Nocturn 3 OT canticles had none at all. Give the 'canticle' ResolvedPart
the same centrally-attached gloriaPatri field psalms already got, strip
the baked-in text, and drop Lauds' now-redundant local append/Triduum
check — live-verified that canticles follow the exact same Triduum-only
omission as psalms (e.g. Benedictus at Lauds of Holy Thursday).

src/hours/types.ts

@@ -204,7 +204,9 @@ export type ResolvedPart =
   // Sacred Triduum (calendar/temporal.ts's isInTriduum) — never omit it
   // when building a psalm part yourself.
   | { kind: 'psalm'; psalmNumber: number; antiphon?: ResolvedText; verses: ResolvedVerse[]; gloriaPatri?: ResolvedText }
-  | { kind: 'canticle'; canticleId: string; text: ResolvedText; antiphon?: ResolvedText }
+  // `gloriaPatri` filled in centrally, same as the 'psalm' kind above —
+  // see that field's doc comment.
+  | { kind: 'canticle'; canticleId: string; text: ResolvedText; antiphon?: ResolvedText; gloriaPatri?: ResolvedText }
   // A standalone antiphon, said on its own rather than framing a psalm —
   // see 'closing-antiphon' above.
   | { kind: 'antiphon'; text: ResolvedText }