feat(ef): the Creed, RG 475-476

Whether the Creed is said at Mass. New Rubrics_ef.creed, reached through
a new Rite.t.creed field and a new Liturgical_day.t.creed bool (false,
not an option, for a rite that has not implemented the rule); colitur
rubrics gains a fourth TAB-separated column.

475(a) reads the TEMPORAL cycle's own weekday, not the observed day: a
Sunday impeded by a Feast of the Lord (RG 16a) still says the Creed.
475(d)'s three octaves (Nativity, Easter, Pentecost) are pure date/
Easter-offset windows, checked first, since a saint's feast winning the
day inside one of them still says the Creed ("etiam in festis
occurrentibus") -- St Stephen, 26 December, is the live witness.

RG 23 classifies Ash Wednesday and every feria of Holy Week (including
the Sacred Triduum) as feriae, not festa, however high their rank, so
475(b)/(c)'s "in festis" never reaches them; this single check subsumes
476(a)'s own naming of the Chrism/Lord's-Supper Mass and the Easter
Vigil. RG 28-34 vigils are a third liturgical-day category, also
excluded from "in festis" regardless of rank -- reuses the already-
exported Precedence_ef.is_vigil rather than a new list.

475(e)'s Apostle/Evangelist natalicia list (creed_apostle_slugs) was
derived by grepping data/ef/sanctoral.sexp directly and checking each
candidate's own date against whether it is that saint's dies natalis --
not copied from any list supplied with the task. The Conversion of St
Paul and the 30 June Commemoration of St Paul are excluded (neither is
a natalicium); the Chair of St Peter and St Barnabas are included only
because the clause names them explicitly, which is exactly why it has
to: neither is a natalicium either.

475(c)'s BVM half reuses Precedence_ef.marian_slugs (newly exported)
rather than the subject field alone: checked against the shipped data,
almost every Marian sanctoral entry ships subject=Saint, not Bvm.

man/colitur.1's rubrics section is updated to match the new column;
test/cli.t repinned via dune promote for the same reason. Verified
day/readings output byte-identical to v0.10.1 across the whole
1583-9999 domain (both binaries' concatenated day+readings output,
6,148,492 lines each, zero diff). Domain-wide: 882,996 days say the
Creed, 2,191,250 do not; every one of the domain's 439,178 Sundays says
it, zero exceptions.

1 files changed, 12 insertions, 2 deletions

diff --git a/bin/main.ml b/bin/main.ml
index e00e020..f957190 100644
--- a/bin/main.ml
+++ b/bin/main.ml
@@ -388,7 +388,16 @@ let readings_line ~lang ~sigla (d : (Rite_ef.Vocab_ef.season, Rite_ef.Vocab_ef.r
    asserted by {!Colitur_kernel.Validate}'s own ["formulary"] check -- but
    the type itself permits [None] (a rite with no lectionary), so this
    prints "-" rather than pattern-matching partially and crashing on a
-   guarantee that belongs to DATA, not to the type. *)
+   guarantee that belongs to DATA, not to the type.
+
+   Task 5 (celebrant-rubrics-phase1): a fourth column, whether the Creed is
+   said (EF: RG 475-476, {!Rite_ef.Rubrics_ef.creed}) -- "true"/"false"
+   ([string_of_bool], not "yes"/"no" or "1"/"0": this row has no other
+   boolean column to be consistent with, so OCaml's own literal is the
+   least surprising choice for a machine-readable field). Unlike
+   [formulary], [d.creed] is a plain [bool] with no [option] to guard: a
+   rite that has not implemented the rule answers [false] outright, so
+   there is no third "unknown" state this column could ever need to print. *)
 let rubrics_line (d : (Rite_ef.Vocab_ef.season, Rite_ef.Vocab_ef.rank) Colitur_kernel.Liturgical_day.t)
     =
   let said, via =
@@ -398,7 +407,8 @@ let rubrics_line (d : (Rite_ef.Vocab_ef.season, Rite_ef.Vocab_ef.rank) Colitur_k
           Colitur_kernel.Mass_formulary.source_to_string f.Colitur_kernel.Mass_formulary.via )
     | None -> ("-", "-")
   in
-  Printf.printf "%s\t%s\t%s\n" (D.to_iso8601 d.Colitur_kernel.Liturgical_day.date) said via
+  Printf.printf "%s\t%s\t%s\t%s\n" (D.to_iso8601 d.Colitur_kernel.Liturgical_day.date) said via
+    (string_of_bool d.Colitur_kernel.Liturgical_day.creed)
 
 (* One civil year, Jan 1 - Dec 31, matching [temporal_report]'s own scan --
    NOT one liturgical year: [Colitur_kernel.Calendar.year] resolves a single