* Commander: make low remaining flight time configurable and do not clear
- add _ACT param to disable/warning/RTL this feature
- publish rtl flight time estimate also in RTL, and thus fix re-validation
- make failure message clearer, distinguish from battery low
* battery check: add hysteresis for declaring battery_low_remaining_time false again
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Signed-off-by: Silvan Fuhrer <silvan@auterion.com>
Co-authored-by: KonradRudin <98741601+KonradRudin@users.noreply.github.com>