Occupancy analytics devices bug (#297)

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## Description

1. Supported new device type `NCPS` in analytics occupancy tab.
2. Fixed a bug where the devices weren't being shown.
3. removed old comment.
4. Increased size of `OccupancyEndSideBar` in medium sized screens.
5. Fixed TVOC code to read data.
6. Changed TVOC unit string to match the device. 
7. Fixed data loading bug in AQI.

## Type of Change

<!--- Put an `x` in all the boxes that apply: -->

- [ ] ✨ New feature (non-breaking change which adds functionality)
- [x] 🛠️ Bug fix (non-breaking change which fixes an issue)
- [x] ❌ Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] 🧹 Code refactor
- [ ] ✅ Build configuration change
- [ ] 📝 Documentation
- [ ] 🗑️ Chore

lib/pages/analytics/modules/air_quality/widgets/aqi_device_info.dart

@@ -65,7 +65,7 @@ class AqiDeviceInfo extends StatelessWidget {
         );
         final tvocValue = _getValueForStatus(
           status,
-          'tvoc_value',
+          'voc_value',
           formatter: (value) => (value / 100).toStringAsFixed(2),
         );
 

lib/pages/analytics/modules/air_quality/widgets/aqi_type_dropdown.dart

@@ -7,7 +7,7 @@ enum AqiType {
   pm25('PM2.5', 'µg/m³', 'pm25'),
   pm10('PM10', 'µg/m³', 'pm10'),
   hcho('HCHO', 'mg/m³', 'cho2'),
-  tvoc('TVOC', 'µg/m³', 'voc'),
+  tvoc('TVOC', 'mg/m³', 'voc'),
   co2('CO2', 'ppm', 'co2');
 
   const AqiType(this.value, this.unit, this.code);