Reorganize includes and use `std::numbers` for math constants

[Piezoid]

• Headers are standalone and can be compiled without additional includes, -> This doesn't mean that all their functionality can be used without needing additional includes. Some argument type are forward declared.
• Added/removed some forward declaration,
• Removed unused includes,
• use std::numbers for math constants (C++20, get rid of M_PI that was required since C++11 on some platforms),
• remove macros.h (contained RUN_ONCE which is no longer used),
• move getTime to the .cpp avoiding the system includes in sites using TimeKeeper.
• Any pointless reordering of include is the result of running git-clang-format on each commit until a fix-point is reached. (I kept a un-formated branch locally, if needed)