Activity log should use domain-aware state labels (e.g. open/closed for door sensors)

[iTerminate]

The activity log shows raw on/off state values regardless of entity domain. For a door/binary_sensor of device_class `door`/`opening`, it should show "open"/"closed" instead of "on"/"off" — matching how Home Assistant itself renders binary_sensor states based on device_class.

Relevant: log entry formatting in the graph/log UI (`src/hatty/ui/graph/`), and the existing binary_sensor label logic in `src/hatty/ui/dashboard/widgets/binary_sensor.py` (`binary_sensor_label`) which already does device_class-aware labeling for the dashboard and could be reused/shared.