feat(cli): colitur rubrics prints the day's Mass formulary

Separate from day for the reason readings is: a formulary name contains
spaces and day's row is space-separated with a variable-length tail.

Modelled on readings' own structure (year parsing, --overlay plumbing,
error handling): --overlay is accepted, since an overlay can change
which celebration is observed and hence which Mass is said. --lang,
--raw and --sigla-* are refused rather than silently ignored -- this
row resolves no display name and no citation for any of them to
affect.

Output is TAB-separated (date, formulary slug, source), not space or
" | " like the two existing reports: a resolved formulary NAME is a
column a later task may add, and it can carry both spaces and
punctuation a citation never does, ruling out either separator already
in use.

day and readings verified byte-identical (sha256) against a v0.10.1
build across 1583/1900/2026/2038/9999. Man page documents rubrics
beside readings and renders through groff with no errors.

1 files changed, 89 insertions, 4 deletions

diff --git a/test/cli.t b/test/cli.t
index bdc19c8..398c6fb 100644
--- a/test/cli.t
+++ b/test/cli.t
@@ -17,7 +17,7 @@ A year outside the supported domain is rejected (exit 2):
 No/garbage arguments give a usage error (exit 2):
 
   $ colitur
-  colitur: usage: colitur easter <year> | colitur temporal <year> | colitur day <year> | colitur readings <year> | colitur emit --format FMT --from Y --to Y | colitur table --year Y --template FILE | colitur render --template FILE --year Y | colitur publish --from Y --to Y --out DIR | colitur lang --list|--dump CODE|--check FILE | colitur config --show | colitur check FILE | colitur new-overlay  (try: colitur --help)
+  colitur: usage: colitur easter <year> | colitur temporal <year> | colitur day <year> | colitur readings <year> | colitur rubrics <year> | colitur emit --format FMT --from Y --to Y | colitur table --year Y --template FILE | colitur render --template FILE --year Y | colitur publish --from Y --to Y --out DIR | colitur lang --list|--dump CODE|--check FILE | colitur config --show | colitur check FILE | colitur new-overlay  (try: colitur --help)
   [2]
 
 The EF temporal cycle for a year, one line per day:
@@ -199,6 +199,91 @@ A year outside the supported domain is rejected (exit 2):
   colitur: year 1000 out of range 1583..9999
   [2]
 
+Rubrics (Task 4, celebrant-rubrics-phase1): the day's own Mass formulary, one
+row per day: date, the formulary's slug (which Mass is actually said, not
+always the day's own), and how that was decided
+(proper/own/preceding-sunday/common/votive). TAB-separated -- not space like
+`day`, not " | " like `readings` -- because a resolved formulary NAME (a
+later column, not this one) can itself contain both spaces and punctuation a
+citation never does, and TAB is what stays unambiguous either way. A
+separate command for the same mechanical reason `readings` is: `day`'s row
+is fixed-width space-separated with a variable-length "+slug" tail.
+
+  $ colitur rubrics 2026 | head -3
+  2026-01-01	ef-circumcision	own
+  2026-01-02	ef-christmas-1-friday	own
+  2026-01-03	ef-christmas-1-saturday	votive
+
+  $ colitur rubrics 2026 | wc -l
+  365
+
+1 January reads "own", not "proper": the Circumcision is a TEMPORAL-origin
+office (Rite_ef.Temporal_ef, not the sanctoral Layer), so step 1 of the
+resolution chain (a SANCTORAL observed celebration's own proper) does not
+apply to it -- step 2 does (the day's own temporal slug in the lectionary),
+tagged `own`. Contrast a real sanctoral saint with his own proper:
+
+  $ colitur rubrics 2038 | grep '^2038-03-08'
+  2038-03-08	john-of-god	proper
+
+A saint with no proper of his own says his assigned Common (step 4):
+
+  $ colitur rubrics 2038 | grep '^2038-03-06'
+  2038-03-06	common-of-non-virgins-1	common
+
+A weekday with no proper of its own resumes the preceding Sunday's, never
+its own observed slug -- 1 December 2025 is the Monday after Advent I, and
+Advent's ferias have no Mass of their own (step 3):
+
+  $ colitur rubrics 2025 | grep '^2025-12-01'
+  2025-12-01	ef-advent-sunday-1	preceding-sunday
+
+3 January 2026 above ("votive") is the RG 78/309(a) Saturday Mass of Our
+Lady, said IN PLACE of the day's own office's Mass while the office (an
+unoccupied IV-class Saturday) itself is kept unchanged -- distinct from
+`own` precisely because a votive Mass is not the day's own, even though
+`said` names the identical slug either way.
+
+A year outside the supported domain is rejected (exit 2):
+
+  $ colitur rubrics 1000
+  colitur: year 1000 out of range 1583..9999
+  [2]
+
+--overlay is accepted, the same reasoning `readings` gets it: an overlay can
+change which celebration is observed, hence which Mass formulary is said.
+Baseline, the unoccupied Saturday says Our Lady's votive Mass; with the
+diocesan overlay's local patron observed instead (no proper or Common of his
+own in the fixture), the chain falls all the way back to step 3:
+
+  $ colitur rubrics 2026 --overlay fixtures/overlay-example-diocesan.sexp | grep '^2026-07-11'
+  2026-07-11	ef-time-after-pentecost-sunday-6	preceding-sunday
+  $ colitur rubrics 2026 | grep '^2026-07-11'
+  2026-07-11	ef-time-after-pentecost-6-saturday	votive
+
+`--lang`/`--raw`/`--sigla-*` are refused rather than silently ignored, unlike
+`readings`: this row resolves no display name and no citation for any of
+them to affect.
+
+  $ colitur rubrics 2026 --lang en
+  colitur: --lang/--raw have no effect on `rubrics`; refusing rather than ignoring them
+  [2]
+
+  $ colitur rubrics 2026 --raw
+  colitur: --lang/--raw have no effect on `rubrics`; refusing rather than ignoring them
+  [2]
+
+  $ colitur rubrics 2026 --sigla-style en
+  colitur: --sigla-style/--sigla-book/--sigla-tradition have no effect on `rubrics`; refusing rather than ignoring them
+  [2]
+
+`colitur day` and `colitur readings` are unaffected by any of the above:
+
+  $ colitur day 2026 --raw | head -1
+  2026-01-01 thursday christmastide - ef-circumcision class-1 white
+  $ colitur readings 2026 --raw | head -1
+  2026-01-01 ef-circumcision | Titus 2:11-15 | Luke 2:21
+
 An explicit COLITUR_DATA_DIR that does not hold the data is an error (exit 2),
 never a silent fall-back to some other copy. A packager or operator who names
 a directory has stated an intent; quietly calendaring off a different one
@@ -247,7 +332,7 @@ The error path is the mirror image -- nothing on stdout, exit 2:
 Every command the help lists is a command the binary actually accepts. This
 is the check that catches help text drifting away from the dispatch:
 
-  $ for c in easter temporal day readings; do colitur $c 2026 > /dev/null || echo "$c FAILED"; done
+  $ for c in easter temporal day readings rubrics; do colitur $c 2026 > /dev/null || echo "$c FAILED"; done
 
 --version prints the version alone, to standard output, exit 0. Deliberately
 not embedded in the help text above: this pin would then have to be edited
@@ -327,14 +412,14 @@ A flag needing a value, given none:
 
   $ colitur day 2026 --overlay
   colitur: --overlay needs a file path
-  colitur: usage: colitur easter <year> | colitur temporal <year> | colitur day <year> | colitur readings <year> | colitur emit --format FMT --from Y --to Y | colitur table --year Y --template FILE | colitur render --template FILE --year Y | colitur publish --from Y --to Y --out DIR | colitur lang --list|--dump CODE|--check FILE | colitur config --show | colitur check FILE | colitur new-overlay  (try: colitur --help)
+  colitur: usage: colitur easter <year> | colitur temporal <year> | colitur day <year> | colitur readings <year> | colitur rubrics <year> | colitur emit --format FMT --from Y --to Y | colitur table --year Y --template FILE | colitur render --template FILE --year Y | colitur publish --from Y --to Y --out DIR | colitur lang --list|--dump CODE|--check FILE | colitur config --show | colitur check FILE | colitur new-overlay  (try: colitur --help)
   [2]
 
 An unknown option is rejected rather than treated as a positional word:
 
   $ colitur day 2026 --diocese
   colitur: unknown option --diocese
-  colitur: usage: colitur easter <year> | colitur temporal <year> | colitur day <year> | colitur readings <year> | colitur emit --format FMT --from Y --to Y | colitur table --year Y --template FILE | colitur render --template FILE --year Y | colitur publish --from Y --to Y --out DIR | colitur lang --list|--dump CODE|--check FILE | colitur config --show | colitur check FILE | colitur new-overlay  (try: colitur --help)
+  colitur: usage: colitur easter <year> | colitur temporal <year> | colitur day <year> | colitur readings <year> | colitur rubrics <year> | colitur emit --format FMT --from Y --to Y | colitur table --year Y --template FILE | colitur render --template FILE --year Y | colitur publish --from Y --to Y --out DIR | colitur lang --list|--dump CODE|--check FILE | colitur config --show | colitur check FILE | colitur new-overlay  (try: colitur --help)
   [2]
 
 The shipped example overlay is runnable documentation, and it must actually