rite(ef): clamp the RG96 search at the domain ceiling

search_from could walk up to 400 days past origin before Calendar's own
~start ~stop clamp is ever consulted, and nothing stopped it probing
occupant on a date past 31 December 9999 -- occupant chains through the
real EF rite's temporal, which calls Computus.gregorian_easter, not
total outside 1583..9999 (it Date.makes and failwiths on Error).

Not reachable with the shipped sanctoral data alone, but reachable
through the project's own primary extension path: an overlay adding an
I-class feast on 25 December leaves nothing but Class2 Nativity-octave
days for the rest of civil year 9999, so the unguarded search reached 1
January of year 10000 and crashed there with 'computus: year 10000 out
of range 1583..9999'. 9999 is an in-range year and the kernel's contract
is 'never raises on in-range input'.

search_from now also stops, without probing occupant again, once it
passes Date's own domain ceiling -- the same 'return a finite date, let
Calendar's own out-of-range handling record it, never pretend to have
found something admissible' contract the existing step-count guard
already follows.

Two new tests, both mutation-verified to actually reproduce the crash
when the guard is removed (see the task report): a precedence_ef.ml unit
test using the real Temporal_ef.temporal as occupant (a synthetic
occupant can never discriminate this, since it never calls Computus
itself), and a Calendar-level integration test reproducing the exact
overlay-based scenario the review found.

1 files changed, 7 insertions, 4 deletions

diff --git a/lib/rites/rite_ef/precedence_ef.mli b/lib/rites/rite_ef/precedence_ef.mli
index d06b058..7318ccd 100644
--- a/lib/rites/rite_ef/precedence_ef.mli
+++ b/lib/rites/rite_ef/precedence_ef.mli
@@ -199,10 +199,13 @@ val annunciation_slug : string
     round guard does not itself enforce (calendar.ml's [place_transfers]
     bounds ROUNDS across a whole year, not one call's internal walk).
     Terminating by a structural bound on the internal walk (max 400 days,
-    an engineering ceiling, not an RG citation -- see the .ml), not by an
-    argument about the real 1962 calendar's own structure, so a rite/data
-    shape this function has not anticipated fails FINITELY rather than
-    hanging the caller. Strictly later than [origin]: the ordinary search
+    an engineering ceiling, not an RG citation -- see the .ml) AND a guard
+    at {!Colitur_kernel.Date}'s own domain ceiling (31 December 9999,
+    beyond which probing [occupant] can itself raise -- see the .ml's
+    [domain_max_date]), not by an argument about the real 1962 calendar's
+    own structure, so a rite/data shape this function has not anticipated
+    fails FINITELY rather than hanging or crashing the caller. Strictly
+    later than [origin]: the ordinary search
     starts at [origin + 1] and only ever advances forward from there; the
     Annunciation's own starting point is provably later than 25 March for
     every representable year (Easter's documented range, register §0) --