Add SERIAL_FLOAT_PRECISION option (#18367)

Marlin/Configuration_adv.h

Marlin/src/MarlinCore.cpp

Marlin/src/core/debug_out.h

Marlin/src/core/macros.h

Marlin/src/core/serial.cpp

Marlin/src/core/serial.h

Marlin/src/core/utility.cpp

Marlin/src/feature/bedlevel/ubl/ubl_G29.cpp

Marlin/src/feature/encoder_i2c.cpp

Marlin/src/feature/encoder_i2c.h

Marlin/src/feature/powerloss.cpp

Marlin/src/gcode/config/M92.cpp

Marlin/src/gcode/feature/advance/M900.cpp

Marlin/src/gcode/probe/G30.cpp

Marlin/src/module/probe.cpp