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/models/analytics_device.dart

@@ -25,8 +25,8 @@ class AnalyticsDevice {
 
   factory AnalyticsDevice.fromJson(Map<String, dynamic> json) {
     return AnalyticsDevice(
-      uuid: json['uuid'] as String,
-      name: json['name'] as String,
+      uuid: json['uuid'] as String? ?? '',
+      name: json['name'] as String? ?? '',
       createdAt: json['createdAt'] != null
           ? DateTime.parse(json['createdAt'] as String)
           : null,
@@ -39,8 +39,8 @@ class AnalyticsDevice {
           ? ProductDevice.fromJson(json['productDevice'] as Map<String, dynamic>)
           : null,
       spaceUuid: json['spaceUuid'] as String?,
-      latitude: json['lat'] != null ? double.parse(json['lat'] as String) : null,
-      longitude: json['lon'] != null ? double.parse(json['lon'] as String) : null,
+      latitude: json['lat'] != null ? double.parse(json['lat'] as String? ?? '0.0') : null,
+      longitude: json['lon'] != null ? double.parse(json['lon'] as String? ?? '0.0') : null,
     );
   }
 }