feat: assert/deassert limit switch in bridged mode

The first implementation was strictly based on how the ZMX crate used to behave. When the limit switch was in bridged mode, the limit switch signal was permanently active, regardless of the opener/closer setting. However, it turned out to be useful for testing purposes to be able to set the signal on the panel hard to LOW.

With the new implementation, the limit switch signal in bridged mode is permanently LOW when the switch is set as opener and permanently HIGH as closer.

doc/modules/ROOT/pages/zmx_user_io_panel.adoc

@@ -25,7 +25,7 @@ The front panel of the ZMX+ Crate accommodates up to sixteen stepper motor drive
 
 The CW & CCW limit switch state LEDs indicate the status of the (high-active) signal that is reported to the motion controller.
 
-The N/B DIP switches are used to set the limit switch mode. In Normal mode, the physical limit switch needs to be active for the state LED to turn ON. In Bridged mode, the physical switch is disregarded, and the state is permanently ON. This mode can be used for hardware commissioning and debugging.
+The N/B DIP switches are used to set the limit switch mode. In Normal mode, the physical limit switch needs to be active for the state LED to turn ON. In Bridged mode, the physical switch is short-circuited so that the status LED remains dark when the switch is configured as Opener and lights up for a Closer. This mode can be used for hardware commissioning and debugging.
 
 The O/C CW & CCW switch specifies the type of limit switch installed. An Opener is expected to break the circuit when the switch is hit, and a Closer will connect in this case.