K dynamic indexing mitigation: check for out of bounds

[FlorianDeconinck]

The new absolute K indexation and write offset in K means we can go out of bounds without the system being able to warn about it since extent calculation won't be able to cover those access.

Think about the degenerate case of

index = some_bad_math_that_gives_back_2349082093840
field[0, 0, value] = value

This was an iron rule for GT4Py that we now allow to be broken so we can match patterns seen regularly in physics.

To mitigate the issue, we should introduce on DEBUG a bound check, drop before every K offset write or absolute read call which should error out cleanly.

Tracking in gt4py: GridTools/gt4py#1684

Parent: GEOS-ESM/SMT-Nebulae#36

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• On DEBUG generate a check for bounds before absolute indexation