Add support for C witness tester

[erhant]

Should be similar to how we wrap the require('circom_tester').wasm, it should wrap .c as well and use one or another based on an optional param. Can default to JS.

[erhant]

https://github.com/erhant/circomkit/blob/main/src/types/index.ts#L54 can add one for C here as well in case there is a difference, and use an intersection interface within Circomkit itself

[erhant]

Prerequisites in my case (Mac M2):

• Install nlohmann-json header that is included within the C code:
• Install nasm
• Install gmp (GNU Multi-precision Arithmetic Library)

Tip

If you are using Mac you can do these with brew:

# install required stuff
brew install nlohmann-json
brew install nasm
brew install gmp

# add brew to path if required, path may differ M2 / M1
export CPLUS_INCLUDE_PATH="$CPLUS_INCLUDE_PATH:/opt/homebrew/include/"
export LIBRARY_PATH="$LIBRARY_PATH:/opt/homebrew/lib"
export INCLUDE_PATH="$INCLUDE_PATH:/opt/homebrew/include"