Fix measurement and locale issues across the app (#1764)

- Fix CLLocation.speed incorrectly labeled as km/h instead of m/s in GPSStatus
- Fix hardcoded Fahrenheit conversion in NodeWeatherForecast to use locale
- Fix altitude chart Y-axis to show feet for imperial locales
- Fix force-unwrap crash risk on locale temperature key in Float extension and calculateDewPoint
- Fix operator precedence confusion in temperature locale checks
- Fix hardcoded kg/mm unit strings to be locale-aware (kg/lbs, mm/in)
- Fix wind speed unit in EnvironmentDefaultColumns to match protobuf m/s
- Fix distance column in EnvironmentDefaultColumns to use Measurement formatter

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: garthvh <1795163+garthvh@users.noreply.github.com>

Author: garthvh

Meshtastic/Extensions/Float.swift

@@ -28,7 +28,7 @@ extension Float {
 		let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
 		var format: UnitTemperature = .celsius
 
-		if localeUnit! as? String == "Fahrenheit" {
+		if (localeUnit as? String) == "Fahrenheit" {
 			format = .fahrenheit
 		}
 		return temperature.converted(to: format).value

Meshtastic/Views/Helpers/Weather/LocalWeatherConditions.swift

@@ -113,7 +113,7 @@ func calculateDewPoint(temp: Float, relativeHumidity: Float, convertToLocale: Bo
 	let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
 	var format: UnitTemperature = .celsius
 
-	if localeUnit! as? String == "Fahrenheit" {
+	if (localeUnit as? String) == "Fahrenheit" {
 		format = .fahrenheit
 	}
 	return dewPointUnit.converted(to: format).value

Meshtastic/Views/Helpers/Weather/NodeWeatherForecast.swift

@@ -27,10 +27,13 @@ struct NodeWeatherForecastView: View {
 		.task {
 			do {
 				let weather = try await WeatherService.shared.weather(for: location, including: .hourly).forecast
+				let locale = NSLocale.current as NSLocale
+				let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
+				let targetUnit: UnitTemperature = (localeUnit as? String) == "Fahrenheit" ? .fahrenheit : .celsius
 				forecast = NodeWeatherForecast(entries: weather.map {
 					.init(
 						date: $0.date,
-						degrees: $0.temperature.converted(to: .fahrenheit).value,
+						degrees: $0.temperature.converted(to: targetUnit).value,
 						isDaylight: $0.isDaylight
 					)
 				})

Meshtastic/Views/Nodes/Helpers/Map/PositionAltitudeChart.swift

@@ -52,7 +52,7 @@ struct PositionAltitudeChart: View {
 					AxisValueLabel("""
 						\(value.as(PlottableMeasurement.self)!
 							.measurement
-							.converted(to: .meters),
+							.converted(to: Locale.current.measurementSystem == .metric ? .meters : .feet),
 								format: .measurement(
 									width: .wide,
 									numberFormatStyle: .number.precision(

Meshtastic/Views/Nodes/Helpers/Metrics Columns/EnvironmentDefaultColumns.swift

@@ -200,7 +200,7 @@ extension MetricsColumnList {
 				tableBody: { _, speed in
 					speed.map {
 						let windSpeed = Measurement(
-							value: Double($0), unit: UnitSpeed.kilometersPerHour)
+							value: Double($0), unit: UnitSpeed.metersPerSecond)
 						return Text(
 							windSpeed.formatted(
 								.measurement(
@@ -289,11 +289,15 @@ extension MetricsColumnList {
 				visible: false,
 				tableBody: { _, distance in
 					distance.map {
-						if UIDevice.current.userInterfaceIdiom == .pad || UIDevice.current.userInterfaceIdiom == .mac {
-							Text(verbatim: "\($0.formatted(.number.grouping(.never).precision(.fractionLength(1)))) mm")
-						} else {
-							Text("\($0.formatted(.number.grouping(.never).precision(.fractionLength(1))))")
-						}
+						let dist = Measurement(
+							value: Double($0), unit: UnitLength.millimeters)
+						return Text(
+							dist.formatted(
+								.measurement(
+									width: .abbreviated,
+									numberFormatStyle: .number.grouping(.never)
+										.precision(
+										.fractionLength(1)))))
 					} ?? Text(Constants.nilValueIndicator)
 				}),
 

Meshtastic/Views/Nodes/Helpers/Metrics Columns/EnvironmentDefaultSeries.swift

@@ -24,7 +24,7 @@ extension MetricsSeriesList {
 				foregroundStyle: { chartRange in
 					let locale = NSLocale.current as NSLocale
 					let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
-					let format: UnitTemperature = localeUnit as? String ?? "Celsius" == "Fahrenheit" ? .fahrenheit : .celsius
+					let format: UnitTemperature = (localeUnit as? String) == "Fahrenheit" ? .fahrenheit : .celsius
 					let lowerBound = chartRange.map { Double($0.lowerBound) } ?? 0.0
 					let upperBound = chartRange.map { Double($0.upperBound) } ?? 100.0
 					let stops: [Gradient.Stop] = generateStops(minTemp: lowerBound, maxTemp: upperBound, tempUnit: format, opacity: 1.0)
@@ -92,7 +92,7 @@ extension MetricsSeriesList {
 				foregroundStyle: { chartRange in
 					let locale = NSLocale.current as NSLocale
 					let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
-					let format: UnitTemperature = localeUnit as? String ?? "Celsius" == "Fahrenheit" ? .fahrenheit : .celsius
+					let format: UnitTemperature = (localeUnit as? String) == "Fahrenheit" ? .fahrenheit : .celsius
 					let lowerBound = chartRange.map { Double($0.lowerBound) } ?? 0.0
 					let upperBound = chartRange.map { Double($0.upperBound) } ?? 100.0
 					let stops: [Gradient.Stop] = generateStops(minTemp: lowerBound, maxTemp: upperBound, tempUnit: format, opacity: 1.0)

Meshtastic/Views/Nodes/Helpers/NodeDetail.swift

@@ -344,15 +344,24 @@ struct NodeDetail: View {
 									RadiationCompactWidget(radiation: radiation.formatted(.number.precision(.fractionLength(1))), unit: "µR/hr")
 								}
 								if let weight = metrics.weight {
-									WeightCompactWidget(weight: weight.formatted(.number.precision(.fractionLength(1))), unit: "kg")
+									let weightMeasurement = Measurement(value: Double(weight), unit: UnitMass.kilograms)
+									let usesMetric = Locale.current.measurementSystem == .metric
+									let weightUnit = usesMetric ? UnitMass.kilograms : UnitMass.pounds
+									let weightLabel = usesMetric ? "kg" : "lbs"
+									WeightCompactWidget(weight: weightMeasurement.converted(to: weightUnit).value.formatted(.number.precision(.fractionLength(1))), unit: weightLabel)
 								}
 								if let distance = metrics.distance {
-									DistanceCompactWidget(distance: distance.formatted(.number.precision(.fractionLength(0))), unit: "mm")
+									let distMeasurement = Measurement(value: Double(distance), unit: UnitLength.millimeters)
+									let usesMetric = Locale.current.measurementSystem == .metric
+									let distUnit = usesMetric ? UnitLength.millimeters : UnitLength.inches
+									let distLabel = usesMetric ? "mm" : "in"
+									let distDecimals = usesMetric ? 0 : 1
+									DistanceCompactWidget(distance: distMeasurement.converted(to: distUnit).value.formatted(.number.precision(.fractionLength(distDecimals))), unit: distLabel)
 								}
 								if let soilTemperature = metrics.soilTemperature {
 									let locale = NSLocale.current as NSLocale
 									let localeUnit = locale.object(forKey: NSLocale.Key(rawValue: "kCFLocaleTemperatureUnitKey"))
-									let unit = localeUnit as? String ?? "Celsius" == "Fahrenheit" ? "°F" : "°C"
+									let unit = (localeUnit as? String) == "Fahrenheit" ? "°F" : "°C"
 									SoilTemperatureCompactWidget(temperature: soilTemperature.localeTemperature().formatted(.number.precision(.fractionLength(0))), unit: unit)
 								}
 								if let soilMoisture = metrics.soilMoisture {

Meshtastic/Views/Settings/GPSStatus.swift

@@ -20,7 +20,7 @@ struct GPSStatus: View {
 		let horizontalAccuracy = Measurement(value: newLocation.horizontalAccuracy, unit: UnitLength.meters)
 		let verticalAccuracy = Measurement(value: newLocation.verticalAccuracy, unit: UnitLength.meters)
 		let altitiude = Measurement(value: newLocation.altitude, unit: UnitLength.meters)
-		let speed = Measurement(value: newLocation.speed, unit: UnitSpeed.kilometersPerHour)
+		let speed = Measurement(value: newLocation.speed, unit: UnitSpeed.metersPerSecond)
 		let speedAccuracy = Measurement(value: newLocation.speedAccuracy, unit: UnitSpeed.metersPerSecond)
 		let courseAccuracy = Measurement(value: newLocation.courseAccuracy, unit: UnitAngle.degrees)