feat: add native local location capture (#4)

Add explicit permission handling, independent continuous and single capture,
location status and deterministic CI coverage.

Final decisions and validation:
https://github.com/jayanezj/traccar-client-macos/issues/4#issuecomment-6399189792

TraccarClient/Interface/LocationStatusView.swift

@@ -0,0 +1,53 @@
+import SwiftUI
+
+struct LocationStatusView: View {
+    let location: LocationModel
+
+    var body: some View {
+        VStack(alignment: .leading, spacing: 16) {
+            Label("Location capture", systemImage: "location")
+                .font(.title2)
+            Text("Capture your Mac's location continuously or once while paused. Nothing is sent to a server.")
+            Text("Choose Start or Capture once to allow macOS to request location permission if needed.")
+                .foregroundStyle(.secondary)
+            Form {
+                LabeledContent("Continuous capture", value: location.continuousRequested ? "Active" : "Paused")
+                LabeledContent("Condition", value: location.status)
+                LabeledContent("Location Services", value: location.availability.services.rawValue)
+                LabeledContent("Permission", value: location.availability.permission.rawValue)
+                LabeledContent("Single capture", value: location.singleStatus.rawValue)
+                if let fix = location.lastFix {
+                    LabeledContent("Fix timestamp", value: fix.timestamp.formatted(date: .numeric, time: .standard))
+                    LabeledContent("Reported accuracy", value: "\(fix.horizontalAccuracy.formatted()) m")
+                    LabeledContent("Source", value: location.lastFixOrigin?.rawValue ?? "Location Services")
+                } else {
+                    Text("No location received.").foregroundStyle(.secondary)
+                }
+            }
+            .formStyle(.grouped)
+            if let error = location.errorMessage ?? location.continuousError {
+                Label(error, systemImage: "exclamationmark.triangle")
+                    .foregroundStyle(.orange)
+            }
+            HStack {
+                Button(location.continuousRequested ? "Pause" : "Start") {
+                    if location.continuousRequested { location.pause() } else {
+                        location.startContinuous()
+                    }
+                }
+                Button("Capture once") {
+                    location.captureOnce()
+                }
+                .disabled(location.singleStatus == .waiting)
+                if location.singleStatus == .waiting {
+                    Button("Cancel capture") { location.cancelSingle() }
+                }
+                Spacer()
+                Button("Refresh status") { location.refreshAvailability() }
+            }
+        }
+        .padding(20)
+        .frame(width: 620, height: 540)
+        .onAppear { location.refreshAvailability() }
+    }
+}

TraccarClient/Interface/SettingsView.swift

@@ -3,6 +3,7 @@ import SwiftUI
 
 struct SettingsView: View {
     @Bindable var model: ConfigurationModel
+    let location: LocationModel
     @State private var focus = WindowFocusController()
 
     var body: some View {
@@ -122,7 +123,7 @@ struct SettingsView: View {
             TextField("Heartbeat (seconds)", value: $model.draft.tracking.heartbeatSeconds, format: .number)
             Toggle("Buffer positions offline", isOn: $model.draft.tracking.bufferingEnabled)
             Toggle("Detect stationary periods", isOn: $model.draft.tracking.stationaryDetectionEnabled)
-            Text("Preferences are saved for later tracking implementation. Tracking remains paused in this build.")
+            Text("Accuracy applies on capture start. Selection, buffering and stationary detection are not active yet.")
         }
         .disabled(!model.hasLoaded)
     }
@@ -132,13 +133,16 @@ struct SettingsView: View {
             Toggle("Launch at login", isOn: $model.draft.tracking.launchAtLogin).disabled(true)
             Toggle("Restore continuous tracking", isOn: $model.draft.tracking.restoreTracking).disabled(true)
             Text("Login startup and tracking restoration will be available in a later build. Both default to off.")
-            Text("Closing Settings keeps the app in the menu bar. Use Quit to exit.")
+            Text("Closing Settings keeps requested capture running in the menu bar. Use Pause to stop capture.")
         }
     }
 
     private var diagnostics: some View {
         Form {
-            LabeledContent("Status", value: "Paused")
+            LabeledContent("Location capture", value: location.continuousRequested ? "Active" : "Paused")
+            LabeledContent("Condition", value: location.status)
+            LabeledContent("Location permission", value: location.availability.permission.rawValue)
+            LabeledContent("Location Services", value: location.availability.services.rawValue)
             LabeledContent("Configuration", value: model.hasLoaded ? "Loaded locally" : "Unavailable")
             Text("Connection and identity: Keychain. Tracking preferences: UserDefaults.")
             Text("No location permission requests or network activity are started by loading or saving settings.")

TraccarClient/Interface/TrackingMenu.swift

@@ -3,15 +3,35 @@ import SwiftUI
 
 struct TrackingMenu: View {
     @Environment(\.openSettings) private var openSettings
+    @Environment(\.openWindow) private var openWindow
+    let location: LocationModel
 
     var body: some View {
-        Text("Paused")
-        Text("Tracking is not available in this build.")
+        Text(location.continuousRequested ? "Location capture active" : "Paused")
+        Text(location.status)
+        Text("Local capture only. No positions are sent.")
+        if let fix = location.lastFix {
+            Text("Last fix: \(fix.timestamp.formatted(date: .numeric, time: .standard))")
+            Text("Reported accuracy: \(fix.horizontalAccuracy.formatted()) m")
+        }
 
         Divider()
 
-        Button("Start tracking") {}
-            .disabled(true)
+        Button(location.continuousRequested ? "Pause location capture" : "Start location capture") {
+            if location.continuousRequested { location.pause() } else if location.availability.canCapture {
+                location.startContinuous()
+            } else {
+                showCaptureWindow()
+            }
+        }
+        Button("Capture location once") {
+            if location.availability.canCapture {
+                location.captureOnce()
+            }
+            showCaptureWindow()
+        }
+        .disabled(location.singleStatus == .waiting)
+        Button("Location status…") { showCaptureWindow() }
         Button("Send location now") {}
             .disabled(true)
         Button("Send SOS") {}
@@ -38,8 +58,14 @@ struct TrackingMenu: View {
         Divider()
 
         Button("Quit Traccar Client macOS") {
+            location.shutdown()
             NSApplication.shared.terminate(nil)
         }
         .keyboardShortcut("q")
     }
+
+    private func showCaptureWindow() {
+        NSApplication.shared.activate()
+        openWindow(id: "location-capture")
+    }
 }