CVE-2024-55565: Predictable results in nanoid generation when given non-integer values

When nanoid is called with a fractional value, there were a number of undesirable effects:

1. in browser and non-secure, the code infinite loops on while (size–)
2. in node, the value of poolOffset becomes fractional, causing calls to nanoid to return zeroes until the pool is next filled
3. if the first call in node is a fractional argument, the initial buffer allocation fails with an error

Version 3.3.8 and 5.0.9 are fixed.