Merge branch 'polish-ui-and-calendar': the gomobile facade and the EF calendar fixes

Two bodies of work that shared a branch.

The gomobile facade (2026-08-03..05): mobile.PartLabels, Days, and the
observed rank on DayInfo, so dlectio stops hardcoding part IDs and rank
strings; the 1962 part labels become i18n data; the documented gomobile
bind command is corrected so it reproduces the shipped .aar.

The EF calendar fixes (2026-08-12): seven defects found by differencing
this engine against colitur, a second 1962 implementation built from the
Missal's General Rubrics rather than from this codebase. RG 96 transfers
were not skipping II-class days; a II-class privileged feria was not
yielding to a feast; Sunday ranks, the two Rose Sundays and Holy Thursday's
colour were wrong; and scripts/gen-sanctoral-ef inferred ranks, deduped
and tagged classes wrongly, which put 15 III-class feasts into the shipped
tridentine-calendar.ini as bare commemorations and dropped four entries
outright.

Holy Thursday was violet in both engines, which is how a shared lineage
hides a defect: this project's ini is generated from missalemeum and
colitur's data was bootstrapped from here, so an error inherited by both
is invisible to a differential. It took the Missal itself to see it.

The EF oracle test now asserts rank and colour, not season alone. One
known gap is recorded in the source rather than fixed, as out of scope:
RG 95 chained transfers (calendar.go).

1 files changed, 92 insertions, 0 deletions

diff --git a/internal/calendar/temporal_ef_test.go b/internal/calendar/temporal_ef_test.go
index 6d632e2..8b1ffa5 100644
--- a/internal/calendar/temporal_ef_test.go
+++ b/internal/calendar/temporal_ef_test.go
@@ -38,3 +38,95 @@ func TestTemporalEFChristTheKing(t *testing.T) {
 		t.Errorf("efChristTheKing(2025) = %s want 2025-10-26", got)
 	}
 }
+
+// TestTemporalEFSundayRanks: RG 11-12 / RG 91 entry 6 -- Sundays of Advent,
+// Lent and Passiontide, and Low Sunday, are I class; all others (including
+// Septuagesima's own three Sundays and the ordinary Sundays after Epiphany/
+// Pentecost) stay II class. Before the fix, only Advent I was I class; every
+// other Advent/Lent Sunday was left at the generic-Sunday II-class default.
+func TestTemporalEFSundayRanks(t *testing.T) {
+	cases := []struct {
+		date string
+		want Rank
+	}{
+		{"2025-11-30", RankClass1}, // Advent I
+		{"2025-12-07", RankClass1}, // Advent II
+		{"2025-12-14", RankClass1}, // Advent III (Gaudete)
+		{"2025-12-21", RankClass1}, // Advent IV
+		{"2025-03-09", RankClass1}, // Lent I
+		{"2025-03-16", RankClass1}, // Lent II
+		{"2025-03-23", RankClass1}, // Lent III
+		{"2025-03-30", RankClass1}, // Lent IV (Laetare)
+		{"2025-04-06", RankClass1}, // Passion Sunday
+		{"2025-04-13", RankClass1}, // Palm Sunday
+		{"2025-04-27", RankClass1}, // Low Sunday
+		{"2025-02-16", RankClass2}, // Septuagesima Sunday -- NOT I class
+		{"2025-02-23", RankClass2}, // Sexagesima Sunday -- NOT I class
+		{"2025-03-02", RankClass2}, // Quinquagesima Sunday -- NOT I class
+		{"2025-06-22", RankClass2}, // II Sunday after Pentecost -- ordinary II class
+	}
+	for _, c := range cases {
+		got := temporalEF(d(c.date))
+		if got.Cel.Rank != c.want {
+			t.Errorf("temporalEF(%s).Cel.Rank = %s, want %s (%s)", c.date, got.Cel.Rank, c.want, got.Cel.Slug)
+		}
+	}
+}
+
+// TestTemporalEFRoseSundays: RG 131 -- rose is permitted on Gaudete (Advent
+// III) and Laetare (Lent IV), for that Sunday's own Office and Mass only.
+// Before the fix, efColour had no Rose case at all.
+func TestTemporalEFRoseSundays(t *testing.T) {
+	if got := temporalEF(d("2025-12-14")).Cel.Colour; got != Rose {
+		t.Errorf("Gaudete (2025-12-14) colour = %s, want rose", got)
+	}
+	if got := temporalEF(d("2025-03-30")).Cel.Colour; got != Rose {
+		t.Errorf("Laetare (2025-03-30) colour = %s, want rose", got)
+	}
+	// The Advent/Lent Sundays either side stay violet -- rose is an indult for
+	// that one Sunday, not a season colour.
+	if got := temporalEF(d("2025-12-07")).Cel.Colour; got != Violet {
+		t.Errorf("Advent II (2025-12-07) colour = %s, want violet", got)
+	}
+	if got := temporalEF(d("2025-03-23")).Cel.Colour; got != Violet {
+		t.Errorf("Lent III (2025-03-23) colour = %s, want violet", got)
+	}
+}
+
+// TestTemporalEFHolyThursdayColour: RG 128(b)/RG 122 -- Holy Thursday's Mass
+// of Chrism and Mass in Cena Domini are white, a whole-day exception to
+// Passiontide's violet. Good Friday and Holy Saturday, either side, stay
+// violet (their own black/no-colour exceptions are a separate, unmodelled
+// gap -- see RG 132, precedence_ef.go's own doc comments).
+func TestTemporalEFHolyThursdayColour(t *testing.T) {
+	easter := d("2025-04-20")
+	holyThu := easter.AddDate(0, 0, -3)
+	goodFri := easter.AddDate(0, 0, -2)
+	holySat := easter.AddDate(0, 0, -1)
+	if got := temporalEF(holyThu).Cel.Colour; got != White {
+		t.Errorf("Holy Thursday colour = %s, want white", got)
+	}
+	if got := temporalEF(goodFri).Cel.Colour; got != Violet {
+		t.Errorf("Good Friday colour = %s, want violet (unchanged)", got)
+	}
+	if got := temporalEF(holySat).Cel.Colour; got != Violet {
+		t.Errorf("Holy Saturday colour = %s, want violet (unchanged)", got)
+	}
+}
+
+// TestTemporalEFEmberDayRanks: RG 91 entry 18 -- the Ember days of Lent (and,
+// unchanged, September and Advent) are II-class privileged ferias, not the
+// ordinary III-class Lenten ferias around them. Before the fix, efEmberSlug
+// had no Lent case at all, so Lent's Ember Wed/Fri/Sat fell through to the
+// ordinary III-class Lenten-feria rank.
+func TestTemporalEFEmberDayRanks(t *testing.T) {
+	// Lent I Sunday 2025 = 2025-03-09; Ember Wed/Fri/Sat = +3/+5/+6.
+	lentI := d("2025-03-09")
+	for _, off := range []int{3, 5, 6} {
+		day := lentI.AddDate(0, 0, off)
+		got := temporalEF(day)
+		if got.Cel.Rank != RankClass2 {
+			t.Errorf("Lent Ember day %s rank = %s, want class-2 (%s)", day.Format("2006-01-02"), got.Cel.Rank, got.Cel.Slug)
+		}
+	}
+}