battery: make time remaining estimation dependent on level flight cha… (#22401)

* battery: make time remaining estimation dependent on level flight characteristis for FW

* battery: fix that FW flight is also correctly detected when vehicle_status is not updated

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>

* FixedwingPositionControl: Move constant to header file

* flight phase estimation: use tecs height rate reference to check for level flight

---------

Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
Co-authored-by: Silvan Fuhrer <silvan@auterion.com>

msg/BatteryStatus.msg

@@ -4,7 +4,7 @@ float32 voltage_v			# Battery voltage in volts, 0 if unknown
 float32 voltage_filtered_v	# Battery voltage in volts, filtered, 0 if unknown
 float32 current_a			# Battery current in amperes, -1 if unknown
 float32 current_filtered_a	# Battery current in amperes, filtered, 0 if unknown
-float32 current_average_a	# Battery current average in amperes, -1 if unknown
+float32 current_average_a	# Battery current average in amperes (for FW average in level flight), -1 if unknown
 float32 discharged_mah		# Discharged amount in mAh, -1 if unknown
 float32 remaining			# From 1 to 0, -1 if unknown
 float32 scale				# Power scaling factor, >= 1, or -1 if unknown

msg/CMakeLists.txt

@@ -93,6 +93,7 @@ set(msg_files
 	FigureEightStatus.msg
 	FailsafeFlags.msg
 	FailureDetectorStatus.msg
+	FlightPhaseEstimation.msg
 	FollowTarget.msg
 	FollowTargetEstimator.msg
 	FollowTargetStatus.msg

msg/FlightPhaseEstimation.msg

@@ -0,0 +1,8 @@
+uint64 timestamp               # time since system start (microseconds)
+
+uint8 flight_phase 		# Estimate of current flight phase
+
+uint8 FLIGHT_PHASE_UNKNOWN = 0  # vehicle flight phase is unknown
+uint8 FLIGHT_PHASE_LEVEL = 1	# Vehicle is in level flight
+uint8 FLIGHT_PHASE_DESCEND = 2	# vehicle is in descend
+uint8 FLIGHT_PHASE_CLIMB = 3   # vehicle is climbing