Commander: Introduce global_position_relaxed (#24280)

To separate accuracy requirements for VTOL hover and cruise.

- global_position_relaxed refers to having a valid horizontal velocity aid source 
in the estimator and a set global reference position, but poses no requirements 
on the accuracy of the provided position estimate. 
- Auto flight modes Mission, Loiter and RTL, while in fixed-wing mode, 
only require the relaxed global position going forward
- COM_POS_FS_EPH is thus no longer used on fixed-wing vehicles (resp. VTOL in FW)
- rename failsafe_flags.local_position_accuracy_low to failsafe_flags.position_accuracy_low
---------

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

ROMFS/px4fmu_common/init.d/rc.fw_defaults

@@ -13,8 +13,6 @@ param set-default MAV_TYPE 1
 #
 # Default parameters for fixed wing UAVs.
 #
-# there is a 2.5 factor applied on the _FS thresholds if for invalidation
-param set-default COM_POS_FS_EPH 50
 param set-default COM_VEL_FS_EVH 3
 
 param set-default COM_POS_LOW_EPH 50

ROMFS/px4fmu_common/init.d/rc.vtol_defaults

@@ -10,9 +10,6 @@ set VEHICLE_TYPE vtol
 # MAV_TYPE_VTOL_FIXEDROTOR 22
 param set-default MAV_TYPE 22
 
-# there is a 2.5 factor applied on COM_POS_FS_EPH if for invalidation
-param set-default COM_POS_FS_EPH 50
-
 param set-default COM_POS_LOW_EPH 50
 
 param set-default MIS_TAKEOFF_ALT 20