PADS_BANK0 GPIO5 had PDE (pull-down enable, bit 2) still set to its
reset default. With both PUE and PDE active the pin floated to ~VDD/2,
causing the Schmitt trigger to read LOW permanently. Clear PDE in
_configure_pad() so the pull-up works correctly.
Added PADS_BANK0_PDE_SHIFT define to rp2350.h.
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).