feat: environment widgets layout redesign with always-visible widgets

- Desktop: 4-in-a-row layout (30/20/20/30 distribution)
- Tablet: 2x2 grid layout
- Mobile: Stacked vertically
- All widgets show "No data available" state instead of being hidden
- Sun position calculates from clock, defaults to 6am/6pm
- Environment refresh changed from 5min to 1 hour

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pubspec.yaml

@@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 1.5.0+1
+version: 1.5.1+1
 
 environment:
   sdk: ^3.10.4