new manual_control_switches msg (split out of manual_control_setpoint) (#16270)

- split out switches from manual_control_setpoint into new message manual_control_switches
 - manual_control_switches published at minimal rate (~ 1 Hz) or immediately on change
 - simple switch debounce in rc_update (2 consecutive identical decodes required)
 - manual_control_switches logged at full rate rather than sampled at (5-10% of messages logged)
 - manual_control_setpoint publish at minimal rate unless changing
 - commander handle landing gear switch for manual modes
 - processing of mode_slot and mode_switch is now split so we only do one or the other (not both)
     - a future step will be to finally drop mode_switch and accompanying switches entirely

Co-authored-by: Matthias Grob <maetugr@gmail.com>

src/modules/logger/logged_topics.cpp

@@ -62,6 +62,7 @@ void LoggedTopics::add_default_topics()
 	add_topic("hover_thrust_estimate", 100);
 	add_topic("input_rc", 500);
 	add_topic("manual_control_setpoint", 200);
+	add_topic("manual_control_switches");
 	add_topic("mission");
 	add_topic("mission_result");
 	add_topic("navigator_mission_item");