v1.9.4

Excess Export now automatically pauses when grid power exceeds 50 W
(house drawing from grid) and resumes once PV production recovers above
house load. This matches the upstream AlphaESS_Excess_Export_Pause /
_Resume automation logic exactly, including a 15 s flap guard and a
requirement for the inverter to be in normal work mode for at least
10 minutes before resuming.

The excess_export_pause switch is replaced by a read-only binary sensor
(binary_sensor.alphaess_inverter_excess_export_pause) that reflects the
auto-pause state. Dashboard examples updated accordingly.