readDoubleLe
Reads a 64-bit IEEE 754 double in little-endian order starting at offset.
The eight bytes are decoded as with readLongLe and reinterpreted through Double.fromBits, so the exact bit pattern is preserved, including NaN payloads written by writeDoubleLe.
Return
the decoded value.
Parameters
offset
the index of the first byte to read.
Throws
if offset is negative or offset + 8 exceeds the array size.