[C++] Lint in CI and various MacOS build improvements

[wjones127]

Summary of Changes

• Added instruction on C++ guide to unset CPATH if on MacOS and using Homebrew. If I did not do that, the build would prefer the header files of Arrow and GTest from homebrew while linking to the shared libraries from Conda, creating linking errors.
• Added ccache.
• Narrowed .clang-tidy checks to exclude the *, which I think selects everything? Or am I wrong about that?
• Run clang-tidy regardless of compiler, including in CI, where it was not previously running.
• Change Flight example port away from 5000 because Apple's Control Center process often occupies that port.

Steps to test on MacOS M1

# clear old environment if needed
conda env remove -n cookbook-cpp

conda create -n cookbook-cpp --file cpp/conda-osx-arm64.lock
conda activate cookbook-cpp

# If using homebrew, need to hide those include paths
unset CPATH

make cpp