v1.6.2

The v1.6.1 coordinator-listener approach could miss the cutoff if the inverter
stopped slightly above the threshold (SOC raw encoding rounding). Converts
force_discharging and force_export to the same refresh pattern as force_import:
send a 60-second dispatch window every 50 seconds, checking SOC before each
re-send. If SOC has reached the cutoff, send reset instead of re-dispatching.
The dispatch therefore expires naturally within 60 seconds at most, returning
the inverter to normal self-consumption mode without relying on an exact SOC
comparison.

Also corrects force_export default fallback SOC from 100% to 4% to prevent
the entity-unavailable edge case from triggering an immediate stop.