feat(of): Christmas-season weekday ferials from catholic-resources.org (date-based)

Completes the seasonal weekday lectionary. The Christmas-season weekdays sit on
the AdventChristmas page in a SHIFTED 6-column layout (Day in c[1], not c[2] like
Advent's 7-column) -- the generator now finds the Day column wherever it is. Adds
date-based slugs to temporal.go: christmas-dec-<29..31> (octave), christmas-jan-<2..7>
(before Epiphany), christmas-after-epiphany-<weekday> (before the Baptism). Fixes
the christmas-octave-fri coverage gap and the by-date/by-week collision.

362/362 seasonal ferial-days render across 2026-2029 with 0 gaps. Extends
TestOFSeasonalFerials. All of Advent/Lent/Easter/Christmas weekdays now CR-sourced;
only the Commons remain (optional -- memorials default to the ferial).

2 files changed, 153 insertions, 0 deletions

diff --git a/internal/caldata/of-lectionary.ini b/internal/caldata/of-lectionary.ini
index 8d36425..41b68cb 100644
--- a/internal/caldata/of-lectionary.ini
+++ b/internal/caldata/of-lectionary.ini
@@ -5000,3 +5000,153 @@ gospel = John 16:16-20
 first = The Acts 18:1-8
 psalm = Psalms 98:1,2-3ab,3cd-4
 gospel = John 16:16-20
+
+[christmas-dec-29-I]
+first = 1 John 2:3-11
+psalm = Psalms 96:1-2a,2b-3,5b-6
+gospel = Luke 2:22-35
+
+[christmas-dec-29-II]
+first = 1 John 2:3-11
+psalm = Psalms 96:1-2a,2b-3,5b-6
+gospel = Luke 2:22-35
+
+[christmas-dec-30-I]
+first = 1 John 2:12-17
+psalm = Psalms 96:7-8a,8b-9,10
+gospel = Luke 2:36-40
+
+[christmas-dec-30-II]
+first = 1 John 2:12-17
+psalm = Psalms 96:7-8a,8b-9,10
+gospel = Luke 2:36-40
+
+[christmas-dec-31-I]
+first = 1 John 2:18-21
+psalm = Psalms 96:1-2,11-12,13
+gospel = John 1:1-18
+
+[christmas-dec-31-II]
+first = 1 John 2:18-21
+psalm = Psalms 96:1-2,11-12,13
+gospel = John 1:1-18
+
+[christmas-jan-2-I]
+first = 1 John 2:22-28
+psalm = Psalms 98:1,2-3ab,3cd-4
+gospel = John 1:19-28
+
+[christmas-jan-2-II]
+first = 1 John 2:22-28
+psalm = Psalms 98:1,2-3ab,3cd-4
+gospel = John 1:19-28
+
+[christmas-jan-3-I]
+first = 1 John 2:29-3:6
+psalm = Psalms 98:1,3cd-4,5-6
+gospel = John 1:29-34
+
+[christmas-jan-3-II]
+first = 1 John 2:29-3:6
+psalm = Psalms 98:1,3cd-4,5-6
+gospel = John 1:29-34
+
+[christmas-jan-4-I]
+first = 1 John 3:7-10
+psalm = Psalms 98:1,7-8,9
+gospel = John 1:35-42
+
+[christmas-jan-4-II]
+first = 1 John 3:7-10
+psalm = Psalms 98:1,7-8,9
+gospel = John 1:35-42
+
+[christmas-jan-5-I]
+first = 1 John 3:11-21
+psalm = Psalms 100:1b-2,3,4,5
+gospel = John 1:43-51
+
+[christmas-jan-5-II]
+first = 1 John 3:11-21
+psalm = Psalms 100:1b-2,3,4,5
+gospel = John 1:43-51
+
+[christmas-jan-6-I]
+first = 1 John 5:5-13
+psalm = Psalms 147:12-13,14-15,19-20
+gospel = Mark 1:7-11
+
+[christmas-jan-6-II]
+first = 1 John 5:5-13
+psalm = Psalms 147:12-13,14-15,19-20
+gospel = Mark 1:7-11
+
+[christmas-jan-7-I]
+first = 1 John 5:14-21
+psalm = Psalms 149:1-2,3-4,5+6a+9b
+gospel = John 2:1-11
+
+[christmas-jan-7-II]
+first = 1 John 5:14-21
+psalm = Psalms 149:1-2,3-4,5+6a+9b
+gospel = John 2:1-11
+
+[christmas-after-epiphany-mon-I]
+first = 1 John 3:22-4:6
+psalm = Psalms 2:7bc-8,10-12a
+gospel = Matthew 4:12-17,23-25
+
+[christmas-after-epiphany-mon-II]
+first = 1 John 3:22-4:6
+psalm = Psalms 2:7bc-8,10-12a
+gospel = Matthew 4:12-17,23-25
+
+[christmas-after-epiphany-tue-I]
+first = 1 John 4:7-10
+psalm = Psalms 72:1-2,3-4,7-8
+gospel = Mark 6:34-44
+
+[christmas-after-epiphany-tue-II]
+first = 1 John 4:7-10
+psalm = Psalms 72:1-2,3-4,7-8
+gospel = Mark 6:34-44
+
+[christmas-after-epiphany-wed-I]
+first = 1 John 4:11-18
+psalm = Psalms 72:1-2,10,12-13
+gospel = Mark 6:45-52
+
+[christmas-after-epiphany-wed-II]
+first = 1 John 4:11-18
+psalm = Psalms 72:1-2,10,12-13
+gospel = Mark 6:45-52
+
+[christmas-after-epiphany-thu-I]
+first = 1 John 4:19-5:4
+psalm = Psalms 72:1-2,14+15bc,17
+gospel = Luke 4:14-22a
+
+[christmas-after-epiphany-thu-II]
+first = 1 John 4:19-5:4
+psalm = Psalms 72:1-2,14+15bc,17
+gospel = Luke 4:14-22a
+
+[christmas-after-epiphany-fri-I]
+first = 1 John 5:5-13
+psalm = Psalms 147:12-13,14-15,19-20
+gospel = Luke 5:12-16
+
+[christmas-after-epiphany-fri-II]
+first = 1 John 5:5-13
+psalm = Psalms 147:12-13,14-15,19-20
+gospel = Luke 5:12-16
+
+[christmas-after-epiphany-sat-I]
+first = 1 John 5:14-21
+psalm = Psalms 149:1-2,3-4,5+6a+9b
+gospel = John 3:22-30
+
+[christmas-after-epiphany-sat-II]
+first = 1 John 5:14-21
+psalm = Psalms 149:1-2,3-4,5+6a+9b
+gospel = John 3:22-30
diff --git a/internal/caldata/of_test.go b/internal/caldata/of_test.go
index 086883a..ca5cc24 100644
--- a/internal/caldata/of_test.go
+++ b/internal/caldata/of_test.go
@@ -95,6 +95,9 @@ func TestOFSeasonalFerials(t *testing.T) {
 		{"easter-octave-mon-I", "Acts 2:14"}, // was absent
 		{"advent-dec-17-I", "Genesis 49"},
 		{"advent-dec-24-I", "2 Samuel 7"},
+		{"christmas-dec-29-I", "1 John 2:3-11"},           // Christmas octave, by date
+		{"christmas-jan-2-I", "1 John 2:22-28"},           // before Epiphany, by date
+		{"christmas-after-epiphany-mon-I", "1 John 3:22"}, // after Epiphany, by weekday
 	} {
 		var first string
 		for _, r := range TemporalReadings("new", tc.key) {