test(scripts): assertion floors for check-type-check-coverage's six families (#15376)

The self-test decided success by `failures.length === 0` alone, so "every
case held" and "the cases never ran" printed the same line. Pin the
registered NAMES: a frozen roster of 56 batteries, each with its own
measured floor, evaluated at the verdict site immediately before the
green line.

The 48 rows of the literal `cases` table are batteries in their own
right (floor 1 each, `registerCase(c.label)` first in the driving loop).
The five families the green line already names are one battery each at
their measured counts -- 57 observation, 45 re-measure, 28 built-closure,
19 auto-lowering, 18 exit-code -- and three assertion blocks the printed
tally does not count get their own batteries so the floor leaves no hole
behind it.

No assertion condition, message or argument changes; both modes are
byte-identical to the installed base on stdout and stderr.


Claude-Session: https://claude.ai/code/session_012zGPuVVX3deAx9LdjK8jCk

Co-authored-by: Claude <noreply@anthropic.com>

Author: claude[bot]