initial control allocation support

- control allocation module with multirotor, VTOL standard, and tiltrotor support
 - angular_velocity_controller
 - See https://github.com/PX4/PX4-Autopilot/pull/13351 for details

Co-authored-by: Silvan Fuhrer <silvan@auterion.com>
Co-authored-by: Roman Bapst <bapstroman@gmail.com>

msg/control_allocator_status.msg

@@ -0,0 +1,21 @@
+uint64 timestamp                        # time since system start (microseconds)
+
+uint8 torque_setpoint_achieved          # Boolean indicating whether the 3D torque setpoint was correctly allocated to actuators. 0 if not achieved, 1 if achieved.
+float32[3] allocated_torque             # Torque allocated to actuators. Equal to `vehicle_torque_setpoint_s::xyz` if the setpoint was achieved.
+float32[3] unallocated_torque           # Unallocated torque. Equal to 0 if the setpoint was achieved.
+                                        # Computed as: unallocated_torque = torque_setpoint - allocated_torque
+
+uint8 thrust_setpoint_achieved          # Boolean indicating whether the 3D thrust setpoint was correctly allocated to actuators. 0 if not achieved, 1 if achieved.
+float32[3] allocated_thrust             # Thrust allocated to actuators. Equal to `vehicle_thrust_setpoint_s::xyz` if the setpoint was achieved.
+float32[3] unallocated_thrust           # Unallocated thrust. Equal to 0 if the setpoint was achieved.
+                                        # Computed as: unallocated_thrust = thrust_setpoint - allocated_thrust
+
+int8 ACTUATOR_SATURATION_OK        =  0 # The actuator is not saturated
+int8 ACTUATOR_SATURATION_UPPER_DYN =  1 # The actuator is saturated (with a value <= the desired value) because it cannot increase its value faster
+int8 ACTUATOR_SATURATION_UPPER     =  2 # The actuator is saturated (with a value <= the desired value) because it has reached its maximum value
+int8 ACTUATOR_SATURATION_LOWER_DYN = -1 # The actuator is saturated (with a value >= the desired value) because it cannot decrease its value faster
+int8 ACTUATOR_SATURATION_LOWER     = -2 # The actuator is saturated (with a value >= the desired value) because it has reached its minimum value
+
+int8[16] actuator_saturation            # Indicates actuator saturation status.
+                                        # Note 1: actuator saturation does not necessarily imply that the thrust setpoint or the torque setpoint were not achieved.
+                                        # Note 2: an actuator with limited dynamics can be indicated as upper-saturated even if it as not reached its maximum value.