Checks INTERVAL qualifiers against the C runtime, and in particular what the
leading field's precision does: the value is written unpadded and then
right-aligned in a width the qualifier decides, so YEAR TO MONTH and YEAR(2) TO
MONTH print alike and YEAR(4) wider. The default leading precision is two for
every field, YEAR included, which this is what establishes.
Three INTERVAL cases are deliberately left out because the C runtime is wrong
about them, and a probe that fails for a known reason stops being useful as a
guard. The file names all three.
run.sh no longer writes its own entry point: the generator emits a static Main
in whichever module holds the 4GL MAIN, so supplying one here would be a second
entry point and the build would refuse to choose.
