feat: add `Float.toBits` and `Float.fromBits`

This PR adds raw transmutation of floating-point numbers to and from `UInt64`. Floats and UInts share the same endianness across all supported platforms. The IEEE 754 standard precisely specifies the bit layout of floats. Note that `Float.toBits` is distinct from `Float.toUInt64`, which attempts to preserve the numeric value rather than the bitwise value.