Add WeatherFormatter unit tests (compass, temperature, hour formatting)

[michaeljolley]

Summary

WeatherFormatter is now the single formatting funnel for all UI surfaces (merged via PR #104). Its CompassDirection modular arithmetic and Hour 12/24h branching currently have zero test coverage.

Proposal

Add WeatherFormatterTests.cs with [DataTestMethod] rows covering:

• Compass boundary cases (0°, 337.5°→360°, each 45° sector)
• Temperature formatting for each unit string
• 12h/24h hour display branching

Benefit

Catches regressions when formatter is touched — critical since all UI surfaces flow through it.

Origin

Squad ideation — May 22, 2026 stand-up.

[michaeljolley]

Closing as already implemented — PR #107 (merged May 21) added comprehensive WeatherFormatterTests.cs covering all the cases described in this issue:

• ✅ Compass boundary cases (0°, 22°, 23°, 45°, 90°, 135°, 180°, 225°, 270°, 315°, 337°, 338°, 360°)
• ✅ Temperature formatting for celsius/fahrenheit
• ✅ 12h/24h hour display branching
• ✅ HighLow formatting
• ✅ Humidity with/without value
• ✅ TemperatureUnit and WindSpeedUnit string mapping

No additional work needed.