Update Stackstrings Algorithm in Go Extraction Code

[Arker123]

The current stackstrings algorithm used in the Go extraction code needs to be updated to improve efficiency and accuracy. The existing implementation might not be optimal for handling certain scenarios and can lead to incorrect results.

[stevemk14ebr]

Stackstrings end up being used extensively in the case of Go obfuscators https://github.com/unixpickle/gobfuscate and https://github.com/burrowers/garble. In each of these strings are replaced with essentially lambda calls that perform an xor loop that when compiled down essentially creates a stack string that is decoded at runtime. If improvements are made to this logic I would love to see focus on these two obfuscators in particular.

As an example:

Note that generally decoding strings such as this involves converting a byte array back into a string, so stackstrings are typically followed by a call to runtime_slicebytetostring