more cross-OS portability by centralizing message API call
enhanced debugging / error message precision (priority groups)
changed my mind, if macro switch then I should AND-mask priority
changed comment on COP0 for `rd > 15` with recalled annotation
macros `SPLIT_CYCLES_VU_FROM_SU`/`USE_MIPS_EXCEPTIONS` are wired in
rewrote CP2 SU emulation + edge fixes / debug checks
stable update