fix(EF): fill reading gaps (major feasts, feria-repeat-through-feast, sundays)

EF readings had ~1.8% of days with no readings (major feasts falling back to
the wrong Sunday, feria-repeats broken when the preceding Sunday was a feast).
Now 0 gaps over 9496 days (2025-2050); reading correctness spot-checks match
missalemeum except the resumed-Epiphany-Sunday edge (next commit).

- calendar.TemporalSlug: the green-season weekday-repeats-the-Sunday rule uses
  the Sunday's TEMPORAL slug, so a Monday still finds its Sunday Mass when that
  Sunday was displaced by a feast (e.g. the Purification on Feb 2).
- Add the missing EF temporal Masses (from missalemeum): the Nativity Day Mass
  (Heb 1:1-12 / John 1:1-14), Epiphany (Isa 60:1-6 / Matt 2:1-12), the Octave
  Day of Christmas (Titus 2:11-15 / Luke 2:21), the 6th Sunday after Epiphany
  (1 Thess 1:2-10 / Matt 13:31-35), and the last Sunday after Pentecost
  (Col 1:9-14 / Matt 24:15-35).

0 files changed, 0 insertions, 0 deletions