Update Boost version to use Filesystem v4

[dimitre]

I've tried to update boost to latest (v1.81.0)
but I think maybe some .a changed names in the meantime
error

cp: stage/lib/libboost_system.a: No such file or directory

With this change we can use boost filesystem v4 which is much more similar to std::filesystem

Today for example of::filesystem::canonical throws error when using boost library and the file doesn't exist.
so when using try / catch we are dealing with unexpected behavior, because sometimes we have to solve canonical paths for non existent files, example: if we are creating a directory.

[ofTheo]

does the stage folder not exist? or just libboost_system.a
if stage/lib exists might be good to list the dir to see what is getting generated.

I often add a bunch of ls -la to see what is being output when debugging issues like this.

[dimitre]

Yes, in fact I'm building locally so the files are already there.

libboost_atomic.a	
libboost_filesystem.a

maybe libboost_system is renamed libboost_atomic?
or maybe the build parameters changed and we have to update cmake invocation?

[ofTheo]

@dimitre it might be that it is not an included lib by default anymore.

on this line we aren't specifying it:
https://github.com/openframeworks/apothecary/blob/master/apothecary/formulas/boost/boost.sh#L46

But we are copying it:
https://github.com/openframeworks/apothecary/blob/master/apothecary/formulas/boost/boost.sh#L312

It might be safe to just do something like this for the copy phase:
cp stage/lib/*.a $1/lib/$TYPE/

[dimitre]

Thank you ! I'll be testing this as a separate PR, so maybe this allows us to use this macro on ofConstants.h

#define BOOST_FILESYSTEM_VERSION 4