Merge branch 'engine-precedence-fixes': OF/EF calendar+readings flawlessness pass

Per-day validation vs litcal (OF) and missalemeum (EF) 2005-2050, all defects
fixed and re-validated to zero: OF calendar 0 real errors forward, OF readings
0 unresolvable, EF 0 reading gaps + resumed Sundays correct.

1 files changed, 21 insertions, 0 deletions

diff --git a/internal/calendar/precedence.go b/internal/calendar/precedence.go
index 3b7c0a6..3c7bf5f 100644
--- a/internal/calendar/precedence.go
+++ b/internal/calendar/precedence.go
@@ -82,6 +82,13 @@ func pick(cands []candidate) (candidate, []candidate) {
 		if pi != pj {
 			return pi < pj
 		}
+		// Within a band, higher liturgical dignity wins (Table of Liturgical Days:
+		// of the Lord, then of the BVM, then of saints) -- so a Lord's solemnity
+		// (Sacred Heart, Corpus Christi) outranks a coinciding saint's solemnity
+		// rather than losing an alphabetical tie.
+		if di, dj := dignity(sorted[i].Cel), dignity(sorted[j].Cel); di != dj {
+			return di < dj
+		}
 		return sorted[i].Cel.Slug < sorted[j].Cel.Slug
 	})
 	// General Norms 60: when two obligatory memorials fall on the same day, both
@@ -108,6 +115,20 @@ func pick(cands []candidate) (candidate, []candidate) {
 	return sorted[0], sorted[1:]
 }
 
+// dignity ranks a celebration within its precedence band by the Table of
+// Liturgical Days' order of dignity: of the Lord (0), of the BVM (1), of saints
+// or unclassified (2).
+func dignity(c Celebration) int {
+	switch c.Class {
+	case ClassLord:
+		return 0
+	case ClassBVM:
+		return 1
+	default:
+		return 2
+	}
+}
+
 // slugIndex returns the position of the candidate with the given slug, or -1.
 func slugIndex(cands []candidate, slug string) int {
 	for i, c := range cands {