Variable DETERMINISM_LEVELS`Const`

DETERMINISM_LEVELS: readonly [
    "none",
    "same-runtime",
    "same-platform",
    "cross-platform",
]

Every DeterminismLevel, in §33's order — which is also weakest to strongest, so DETERMINISM_LEVELS.indexOf(a) >= DETERMINISM_LEVELS.indexOf(b) reads "tier a is at least as strong as tier b".