docs: close the final review's four documentation residues

precedence_ef.mli said "there is no fifth, unclassified case" after the
same commit renumbered the disposition list from four cases to five; the
count is now six.

precedence.mli's physical-equality obligation described the failure mode
as counting a drop "a SECOND time (once because it is genuinely absent,
once because its identity no longer matches)" -- the same condition
stated twice. What actually happens to a rebuilt candidate record is
that the celebration surfaces in BOTH commemorations (the copy) and
omitted (the original), one admission double-reported. precedence_ef.ml
carried the same muddled sentence, which is where the kernel's copy came
from; both now say it plainly.

vocab.ml/.mli referenced {!Rite_ef.rite_ef.ml} -- a filename inside an
odoc reference, which is malformed. Now plain [Rite_ef.rite].

README documented only `dune test`, so the exhaustive 1583-9999 Validate
sweep was discoverable only by reading test_validate.ml's own comment.
With no CI in this repo, that line is what stands between a committed
artifact and one anyone runs.

No behaviour change: `colitur day` output is byte-identical across 1583,
1900, 1902, 2008, 2011, 2026, 2038 and 9999 (2921 days, both domain
edges). 259 tests by default, 260 with the sweep.

0 files changed, 0 insertions, 0 deletions