Public function docstrings belong exclusively in .h headers per
coding convention. Only static helper functions and static variables
retain docstrings in .c files. Removed 413 duplicate docstrings
across 185 files (15 CBM + 15 C SDK projects). All 30 projects
rebuild with zero errors.
No project uses floating-point, so coprocessor_enable() was dead code.
Removes rp2350_coprocessor.c/.h and all references from reset handlers
and Makefiles across all 15 CBM drivers (0x01-0x0f).