fix(rite-ef): band has no table entry for a bare commemoration, ever

Fix round 1 on the commemoration-identity/tie-break work: the "genuine
same-band tie" M17 adjudicated as open was not a tie at all. RG 91's
table enumerates only "dies liturgici" (real feasts) -- entry 24's own
text is "Festa III classis, in calendario Ecclesiae universae
inscripta" -- so a Celebration.t.status = Commemoration_only candidate
(a saint reduced to a bare commemoration) has no row in the table to
begin with. Precedence_ef.band used to read rank alone, so it silently
lent such a candidate the same table entry as a genuine Feast of its
own rank; the calendarium's own 22 September row confirms the
distinction in its own notation ("S. Thomae de Villanova ... III
classis. / Commemoratio Ss. Mauritii et Soc. Mm." -- Thomas carries a
class number, Maurice carries none).

Fixed at the source, not by adding a status tier to compare_precedence:
band now checks status first, ahead of every rank-keyed branch, and
returns unclassified for any Commemoration_only candidate. M17 deleted
(not re-adjudicated) -- 22 September now resolves identically on both
sides, with no divergence left to name.

Blast radius measured independently (a temporary git worktree at the
pre-fix commit): 4451 days change across the whole 1583-9999 domain,
exactly 4 verified shapes -- 3576 x maurice-and-companions-martyrs ->
thomas-of-villanova and 282 x eleutherius -> philip-neri (admitted set
changes), 502 x appollonia/cyril-of-alexandria and 91 x dorothy/titus
(order only, independently confirmed against the calendarium's own
listing convention). Zero days change who is observed. Further swept
the whole domain for a genuine "two different candidates on the
identical real table entry" residual -- the shape RG 113 truly gives
no instruction for -- and found it empty: of 109201 same-rank ties
domain-wide, 83950 now resolve by band alone and the remaining 25251
are exclusively two Commemoration_only candidates tied at unclassified,
never two real feasts. The residual admit still breaks alphabetically
is real, but narrower than previously documented.

The "66 days" figure is reconciled, not merely disputed: 599 is the
tie population, 65 (whole-comparator: 67) is the real admitted-set
decision count within it (independently reproduced against the
pre-Task-B binary), 149 is order-only. Every one of the 65 real
decisions traces to the same Commemoration_only/Feast root cause as
Maurice/Thomas.

Also: validate.ml's admission fixed-point check recovers a
commemoration's real origin (by matching its slug against the day's
own temporal office) instead of reconstructing every candidate as
Sanctoral, since band -- unlike EF's own admit -- does read origin;
precedence_ef.ml/.mli's motivating example and blast-radius claims
corrected to no longer rest on the fixed Maurice/Thomas case;
test_identity_rank_corroboration's own population count corrected now
that 22 September (and 21 other Feast-status matches) became reachable;
its rank-agreement pin documents exactly what it does and does not
prove. Register (§4, §6.1, §6 checklist) and CLAUDE.md corrected in
place, including the RG 113 first-sentence gap this exercise surfaced
but did not close, recorded as a new open item.

275 -> 276 tests (with the exhaustive sweep), all green.

1 files changed, 36 insertions, 8 deletions

diff --git a/lib/rites/rite_ef/precedence_ef.mli b/lib/rites/rite_ef/precedence_ef.mli
index 49195f9..b283a17 100644
--- a/lib/rites/rite_ef/precedence_ef.mli
+++ b/lib/rites/rite_ef/precedence_ef.mli
@@ -68,10 +68,21 @@ val unclassified : int
     text states an exception: entry 8 (All Souls) reads "yields to an
     occurring Sunday", so on a Sunday this returns a value that
     loses to entry 15 rather than the literal integer 8 (see the comment on
-    entry 8 in precedence_ef.ml for the exact value and why). Total over
-    every candidate {!Precedence.resolve} or {!Calendar} can construct,
-    including shapes the 1962 table itself does not describe (see
-    {!unclassified}). *)
+    entry 8 in precedence_ef.ml for the exact value and why). ALSO
+    {!unclassified} for any [Cel.Commemoration_only] candidate, checked
+    first, ahead of every rank-keyed branch -- CORRECTED, Task B fix round
+    1 (coordinator finding 1): RG 91's own table enumerates only "dies
+    liturgici" (entry 24's own text, "Festa III classis..." -- FEASTS), so
+    a celebration reduced to a bare commemoration was never a row in the
+    table to begin with, confirmed by the calendarium's own notation (a
+    genuine feast carries a class number on its occurrence line; a bare
+    "Commemoratio" carries none). Before this fix, a [Commemoration_only]
+    candidate silently borrowed the SAME entry number as a genuine [Feast]
+    of its own [rank] -- manufacturing ties {!Precedence.compare_by} and
+    {!compare_precedence} both then had to break some other way, that RG 91
+    itself never created. Total over every candidate {!Precedence.resolve}
+    or {!Calendar} can construct, including shapes the 1962 table itself
+    does not describe (see {!unclassified}). *)
 val band : Vocab_ef.season Precedence.context -> Vocab_ef.rank Precedence.candidate -> int
 
 (** RG 33's marker: every Sunday slug this rite's temporal cycle produces
@@ -195,8 +206,16 @@ val september_ember_prefix : string
     CORRECTED, Task B (branch ef-rg16a): this used to sort by
     [Vocab_ef.rank] (RG 8's coarse four-class "dignity") and break same-rank
     ties alphabetically by slug -- an engineering convention with no
-    rubrical warrant, cited nowhere, silently deciding 66 days over
-    2005-2050. RG 113's own second sentence, previously uncited
+    rubrical warrant, cited nowhere. Measured, fix round 1 (2005-2050,
+    reproducible via a temporary [git worktree] at the pre-fix commit):
+    a same-[rank] tie existed in the candidate pool offered to [admit] on
+    599 days, most never reaching a real decision (RG 111's own admission
+    count often has room for both, e.g. a III-class day admits two); of
+    those, reversing the slug tie-break ALONE actually changed the ADMITTED
+    SET on 65 days and only the printed ORDER of an already-admitted pair
+    on a further 149 (docs/research/rules-register.md §6.1's own full
+    account, superseding this comment's earlier, unreproduced "66 days"
+    claim). RG 113's own second sentence, previously uncited
     (docs/research/rules-register.md §4's RG 113 entry), is the real rule:
     *"in admittendis et ordinandis aliis commemorationibus, servetur ordo
     tabellae praecedentiae"* -- admitting and ordering commemorations both
@@ -205,8 +224,17 @@ val september_ember_prefix : string
     receive on its own, so {!Precedence.resolve} computes it once,
     generically, and hands each candidate its own value as the trailing
     [int] on [comms]'s triples (see {!Precedence.rules.admit}). Ties break
-    on slug ONLY within one identical [band] value (RG 113 gives no further
-    instruction there; still an uncited engineering convention, register §6
+    on slug ONLY within one identical [band] value -- CORRECTED, fix round
+    1 (coordinator finding 1): [band] itself used to hand a
+    [Cel.Commemoration_only] candidate the same table entry as a genuine
+    [Cel.Feast] of its own rank (RG 91's table has no row for a bare
+    commemoration at all), manufacturing most of the "identical [band]
+    value" ties this comment used to describe as RG 113's own residual.
+    Fixed in [band] itself; checked afterward (2005-2050 and the full
+    1583-9999 domain, register §6.1) and found EMPTY of any remaining
+    "two different real table entries tied" case -- the slug fallback below
+    is exercised only between two [Commemoration_only] candidates both at
+    {!unclassified}, still an uncited engineering convention (register §6
     "RG 113 tie-break"), matching {!Precedence.compare_by}'s own fallback,
     so the result never depends on the order [comms] arrives in.