kinematics: Generic Cartesian kinematics implementation (#6815)

* tests: Added a regression test for generic_cartesian kinematics

* kinematics: An intial implementation of generic_cartesian kinematics

* generic_cartesian: Refactored kinematics configuration API

* generic_cartesian: Use stepper instead of kinematic_stepper in configs

* generic_cartesian: Added SET_STEPPER_KINEMATICS command

* generic_cartesian: Fixed parsing of section names

* docs: Generic Caretsian kinematics documentation and config samples

* generic_cartesian: Implemented multi-mcu homing validation

* generic_cartesian: Fixed typos in docs, minor fixes

* generic_cartesian: Renamed `kinematics` option to `carriages`

* generic_cartesian: Moved kinematic_stepper.py file

* idex_modes: Internal refactoring of handling dual carriages

* stepper: Refactored the code to not store a reference to config object

* config: Updated example-generic-cartesian config

* generic_cartesian: Restricted SET_STEPPER_CARRIAGES and exported status

* idex_modes: Fixed handling stepper kinematics with input shaper enabled

* config: Updated configs and tests for SET_DUAL_CARRIAGE new params

* generic_cartesian: Avoid inheritance in the added classes

Signed-off-by: Dmitry Butyugin <dmbutyugin@google.com>

klippy/kinematics/polar.py

@@ -11,7 +11,7 @@ class PolarKinematics:
         # Setup axis steppers
         stepper_bed = stepper.PrinterStepper(config.getsection('stepper_bed'),
                                              units_in_radians=True)
-        rail_arm = stepper.PrinterRail(config.getsection('stepper_arm'))
+        rail_arm = stepper.LookupRail(config.getsection('stepper_arm'))
         rail_z = stepper.LookupMultiRail(config.getsection('stepper_z'))
         stepper_bed.setup_itersolve('polar_stepper_alloc', b'a')
         rail_arm.setup_itersolve('polar_stepper_alloc', b'r')