七麦数据

## [1.3] - 2025-08-11

### Added
- **Fractional Visibility Support**: Enhanced METAR parsing to correctly handle fractional visibility values (e.g., "3/4SM", "1 1/4SM")
- **Low Level Wind Shear (LLWS) Detection**: Added comprehensive parsing and display of wind shear information from raw METAR data
- **CAVOK Condition Handling**: Implemented support for "Ceiling And Visibility OK" conditions, displaying "Visibility OK" and "Ceiling OK" appropriately
- **Density Altitude Calculation**: Added computed density altitude field using precise aviation formula including temperature, pressure, humidity, and airport elevation
- **Airport Elevation Integration**: Enhanced airport data loading to include elevation information from airports.csv for accurate density altitude calculations
- **Enhanced UI Layout**: Improved readability and alignment across iPhone and iPad interfaces

### Changed
- **iPhone Landscape Layout**: Reorganized weather information into logical rows for better readability:
- Row 1: METAR Age
- Row 2: Temperature, Dew Point, Wind
- Row 3: Visibility, Altimeter, Density Altitude
- Row 4: Clouds, RVR, LLWS, Weather Phenomena
- **iPad Layout Optimization**: Split main weather line into multiple rows for improved readability and consistent alignment
- **Visibility Parsing**: Updated regex patterns to handle fractional visibility values with improved accuracy
- **Flight Category Logic**: Enhanced to properly handle CAVOK conditions and fractional visibility values
- **Density Altitude Formula**: Implemented precise calculation using WMO vapor pressure formula and airport elevation

### Fixed
- **Fractional Visibility Bug**: Corrected issue where "3/4SM" was incorrectly interpreted as "4SM"
- **LLWS Display**: Fixed wind shear information parsing and display with appropriate labeling ("Wind Shear" vs "Low Level Wind Shear")
- **UI Alignment Issues**: Resolved inconsistent spacing and alignment across different device orientations
- **Cloud Info Alignment**: Fixed alignment of cloud information field in iPad view to match other row elements
- **Caching Issues**: Temporarily reduced cache expiration for testing and debugging density altitude calculations
- **Airport Elevation Parsing**: Fixed parsing of decimal elevation values from CSV file

### Technical Improvements
- **Enhanced Regex Patterns**: Improved pattern matching for visibility, wind shear, and other METAR elements
- **Debug Logging**: Added comprehensive debug output for density altitude calculations and airport elevation loading
- **Data Structure Updates**: Extended MetarData and DetailedWeather structs to include new fields (llws, densityAltitude)
- **Error Handling**: Improved error handling for edge cases in METAR parsing and calculations

Fixed few bugs. Improved the airport list to only display the one with METAR/TAF.
Improved the overall response time on the selection of airports.

Few bugs corrected.