Census the sqllogictest skips a run's own summary cannot report - #127

WITNESS: MobilityDuck main 238040ab2 carries 14 `mode skip` directives across
its test files, and the summary its CI writes reports 102 test cases and no
skip at all. The directive silences every statement after it to the end of the
file or to a `mode unskip`, while the file still counts as one PASSING test
case -- so no log-reading check can see it, whatever dialect it reads.

A SECOND FINDING THE FIXTURE EXPOSED: `.test` belongs to no suffix set, so
`is_text` refuses a sqllogictest file and NO rule of this check reads one. The
first draft of the pattern therefore found nothing over a fixture carrying the
directive outright, and the suffix is what makes the census possible at all.

MEASURED: the rule reads 14 findings over that tree, one per directive, which
is what an anchored grep of the same tree counts. MEOS-API's own tree stays at
0 -- its two prose mentions of the directive sit inside comments, and the
pattern anchors to the start of a line because that is where a directive
stands. A fixture carrying the directive fails while a fixture naming it in a
comment passes, so the census discriminates the two rather than counting the
word.

The finding message becomes per-pattern: a build flag publishes an artefact
from a suite that never ran, while this directive leaves the suite running and
silent, and one sentence cannot state both.

WHY: the log guard and this census answer different questions, and only the
pair covers a sqllogictest consumer. A guard reading the run's summary alone
answers `0 skipped` over all 14, which is a green tick placed exactly where the
coverage left.