FIX underlying changes

What's was fixed

Sometimes when underlying switch is manually activated, the device state is not updated on Solar Optimizer.

Add unit test and fix no state on startup

What is new:

1. some unit testing have been implemented,
2. the running the bug in which no state are sometimes available on startup,
3. add the hacs.json file in order to prepare the publication into HACS repo.

Fix set enable state

Cf title

FIX set enable not propagated

Cf. title

Enhancements at startup and add duration_stop_min parameter

New features

---

FR

• ajout du paramètre duration_stop_min qui permet de spécifier une durée minimale de désactivation pour le distinguer du délai minimal d'activation duration_min. Si non spécifié, ce paramètre prend la valeur de duration_min.
• restaure l'état des switchs enable au démarrage de l'intégration.
• lance un calcul immédiatement après le démarrage de Home Assistant

---

EN

• added the duration_stop_min parameter, which allows specifying a minimum deactivation duration to differentiate it from the minimum activation delay duration_min. If not specified, this parameter takes on the value of duration_min.
• restores the state of the enable switches upon integration startup.
• initiates a calculation immediately after Home Assistant starts.

FIX NPE in sensor

If no calculation is done (production is not available for example), a NullPointerException occurs in sensor.py:

2023-08-04 21:23:28.414 ERROR (MainThread) [homeassistant] Error doing job: Task exception was never retrieved
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/helpers/update_coordinator.py", line 229, in _handle_refresh_interval
    await self._async_refresh(log_failures=True, scheduled=True)
  File "/usr/src/homeassistant/homeassistant/helpers/update_coordinator.py", line 374, in _async_refresh
    self.async_update_listeners()
  File "/usr/src/homeassistant/homeassistant/helpers/update_coordinator.py", line 164, in async_update_listeners
    update_callback()
  File "/config/custom_components/solar_optimizer/sensor.py", line 57, in _handle_coordinator_update
    value = self.coordinator.data.get(self.idx)
            ^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'get'

FIX error when production is None

This release fix an error log when the production cannot be calculated and is None.

Add sensors units

Add units to sensors.

Smooth optionnaly the solar production and add reconfiguration

Add following features:

1. Smooth optionnaly the solar production to avoid too much change (usefull in cloudy environment),
2. add reconfiguration of thhe integration.

First release published

See README.md for all features.