The value to validate.
true if the value is a safe integer.
A safe integer is an integer that can be exactly represented within JavaScript's IEEE-754 double-precision range:
-(2^53 - 1) to 2^53 - 1
[ [-(2^{53}-1),\ 2^{53}-1] ]
isSafeInteger(42); // true
isSafeInteger(Number.MAX_SAFE_INTEGER); // true
isSafeInteger(Number.MAX_SAFE_INTEGER + 1); // false
Determines whether the provided value is a safe integer number.