Feature: Add Kiosk Mode core manager and integration

Part 2 of Kiosk Mode implementation. Depends on PR home-assistant#4197.

## KioskModeManager (~970 lines)
Central coordinator for all kiosk functionality:
- Enable/disable kiosk mode
- Screen state management (on, dimmed, screensaver)
- Brightness control with day/night scheduling
- Idle timer and activity tracking
- Dashboard navigation
- Entity trigger subscriptions
- HA WebSocket integration

## Security (~760 lines)
- SecurityManager: PIN and biometric authentication
- SettingsManager: Settings persistence

## Dashboard (~360 lines)
- DashboardManager: Dashboard rotation and scheduling

## Camera Detection (~320 lines)
- CameraDetectionManager: Motion and presence detection using front camera

## App Launcher (~360 lines)
- AppLauncherManager: Launch external apps, return handling

## WebViewController Integration (~565 lines)
- WebViewController+Kiosk: Kiosk overlay management
- Modified WebViewController: Made properties internal for kiosk access

Author: nstefanelli

HomeAssistant.xcodeproj/project.pbxproj

@@ -0,0 +1,361 @@
+import Combine
+import Foundation
+import Shared
+import UIKit
+import UserNotifications
+
+// MARK: - App Launcher Manager
+
+/// Manages external app launching, return timeout, and away state tracking
+@MainActor
+public final class AppLauncherManager: ObservableObject {
+    // MARK: - Singleton
+
+    public static let shared = AppLauncherManager()
+
+    // MARK: - Published State
+
+    /// Current app state (active, away, background)
+    @Published public private(set) var appState: AppState = .active
+
+    /// Whether the app is currently "away" (another app was launched)
+    @Published public private(set) var isAway: Bool = false
+
+    /// The app that was launched (if tracking)
+    @Published public private(set) var launchedApp: AppShortcut?
+
+    /// Time when the app was launched
+    @Published public private(set) var launchTime: Date?
+
+    /// Time remaining on return timeout (if active)
+    @Published public private(set) var returnTimeRemaining: TimeInterval = 0
+
+    // MARK: - Notifications
+
+    public static let appStateDidChangeNotification = Notification.Name("AppLauncherManager.appStateDidChange")
+    public static let didReturnFromAppNotification = Notification.Name("AppLauncherManager.didReturnFromApp")
+
+    // MARK: - Callbacks
+
+    /// Called when return timeout expires
+    public var onReturnTimeoutExpired: (() -> Void)?
+
+    /// Called when user returns from launched app
+    public var onReturnFromApp: ((AppShortcut?) -> Void)?
+
+    // MARK: - Private
+
+    private var settings: KioskSettings { KioskModeManager.shared.settings }
+    private var returnTimer: Timer?
+    private var countdownTimer: Timer?
+    private var sceneObservers: [NSObjectProtocol] = []
+
+    // MARK: - Initialization
+
+    private init() {
+        setupSceneObservers()
+        requestNotificationPermission()
+    }
+
+    deinit {
+        sceneObservers.forEach { NotificationCenter.default.removeObserver($0) }
+    }
+
+    // MARK: - Public Methods
+
+    /// Launch an app by URL scheme
+    public func launchApp(urlScheme: String, shortcut: AppShortcut? = nil) -> Bool {
+        guard let url = URL(string: urlScheme) else {
+            Current.Log.warning("Invalid URL scheme: \(urlScheme)")
+            return false
+        }
+
+        return launchApp(url: url, shortcut: shortcut)
+    }
+
+    /// Launch an app by URL
+    public func launchApp(url: URL, shortcut: AppShortcut? = nil) -> Bool {
+        guard UIApplication.shared.canOpenURL(url) else {
+            Current.Log.warning("Cannot open URL: \(url)")
+            return false
+        }
+
+        Current.Log.info("Launching app: \(url.absoluteString)")
+
+        // Record the launch
+        launchedApp = shortcut
+        launchTime = Date()
+        isAway = true
+        appState = .away
+
+        // Start return timeout if configured
+        startReturnTimeout()
+
+        // Open the URL
+        UIApplication.shared.open(url, options: [:]) { success in
+            if !success {
+                Current.Log.warning("Failed to open URL: \(url)")
+                Task { @MainActor in
+                    self.cancelAwayState()
+                }
+            }
+        }
+
+        // Record activity
+        KioskModeManager.shared.recordActivity(source: "app_launch")
+
+        // Notify
+        NotificationCenter.default.post(name: Self.appStateDidChangeNotification, object: nil)
+
+        return true
+    }
+
+    /// Launch an app shortcut
+    public func launchShortcut(_ shortcut: AppShortcut) -> Bool {
+        launchApp(urlScheme: shortcut.urlScheme, shortcut: shortcut)
+    }
+
+    /// Return to Home Assistant (called when app becomes active again)
+    public func handleReturn() {
+        guard isAway else { return }
+
+        Current.Log.info("Returned from app: \(launchedApp?.name ?? "unknown")")
+
+        cancelReturnTimeout()
+
+        let returnedFromApp = launchedApp
+        launchedApp = nil
+        launchTime = nil
+        isAway = false
+        appState = .active
+        returnTimeRemaining = 0
+
+        // Notify
+        onReturnFromApp?(returnedFromApp)
+        NotificationCenter.default.post(
+            name: Self.didReturnFromAppNotification,
+            object: nil,
+            userInfo: ["app": returnedFromApp as Any]
+        )
+        NotificationCenter.default.post(name: Self.appStateDidChangeNotification, object: nil)
+
+        // Record activity
+        KioskModeManager.shared.recordActivity(source: "app_return")
+    }
+
+    /// Cancel away state without triggering return callbacks
+    public func cancelAwayState() {
+        cancelReturnTimeout()
+        launchedApp = nil
+        launchTime = nil
+        isAway = false
+        appState = .active
+        returnTimeRemaining = 0
+    }
+
+    /// Get all configured app shortcuts
+    public var shortcuts: [AppShortcut] {
+        settings.appShortcuts
+    }
+
+    /// Check if an app can be launched
+    public func canLaunch(urlScheme: String) -> Bool {
+        guard let url = URL(string: urlScheme) else { return false }
+        return UIApplication.shared.canOpenURL(url)
+    }
+
+    /// Get duration since app was launched
+    public var awayDuration: TimeInterval? {
+        guard let launchTime else { return nil }
+        return Date().timeIntervalSince(launchTime)
+    }
+
+    // MARK: - Private Methods
+
+    private func setupSceneObservers() {
+        // Observe app becoming active (returning from another app)
+        let activeObserver = NotificationCenter.default.addObserver(
+            forName: UIScene.didActivateNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] _ in
+            self?.handleSceneActivation()
+        }
+        sceneObservers.append(activeObserver)
+
+        // Observe app going to background
+        let backgroundObserver = NotificationCenter.default.addObserver(
+            forName: UIScene.didEnterBackgroundNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] _ in
+            self?.handleSceneBackground()
+        }
+        sceneObservers.append(backgroundObserver)
+
+        // Observe app becoming inactive
+        let inactiveObserver = NotificationCenter.default.addObserver(
+            forName: UIScene.willDeactivateNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] _ in
+            self?.handleSceneDeactivation()
+        }
+        sceneObservers.append(inactiveObserver)
+    }
+
+    private func handleSceneActivation() {
+        if isAway {
+            handleReturn()
+        } else if appState == .background {
+            appState = .active
+            NotificationCenter.default.post(name: Self.appStateDidChangeNotification, object: nil)
+        }
+    }
+
+    private func handleSceneBackground() {
+        if !isAway {
+            appState = .background
+            NotificationCenter.default.post(name: Self.appStateDidChangeNotification, object: nil)
+        }
+    }
+
+    private func handleSceneDeactivation() {
+        // This fires when the app is about to go to background
+        // Don't change state here - wait for didEnterBackground
+    }
+
+    // MARK: - Return Timeout
+
+    private func startReturnTimeout() {
+        let timeout = settings.appLaunchReturnTimeout
+        guard timeout > 0 else { return }
+
+        cancelReturnTimeout()
+        returnTimeRemaining = timeout
+
+        Current.Log.info("Starting return timeout: \(Int(timeout)) seconds")
+
+        // Countdown timer for UI updates
+        countdownTimer = Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { [weak self] _ in
+            Task { @MainActor in
+                guard let self else { return }
+                if self.returnTimeRemaining > 0 {
+                    self.returnTimeRemaining -= 1
+                }
+            }
+        }
+
+        // Main timeout timer
+        returnTimer = Timer.scheduledTimer(withTimeInterval: timeout, repeats: false) { [weak self] _ in
+            Task { @MainActor in
+                self?.handleReturnTimeout()
+            }
+        }
+
+        // Schedule local notification
+        scheduleReturnNotification(timeout: timeout)
+    }
+
+    private func cancelReturnTimeout() {
+        returnTimer?.invalidate()
+        returnTimer = nil
+        countdownTimer?.invalidate()
+        countdownTimer = nil
+        returnTimeRemaining = 0
+
+        // Cancel pending notification
+        cancelReturnNotification()
+    }
+
+    private func handleReturnTimeout() {
+        Current.Log.info("Return timeout expired")
+
+        cancelReturnTimeout()
+        onReturnTimeoutExpired?()
+
+        // The notification will alert the user to return
+    }
+
+    // MARK: - Local Notifications
+
+    private func requestNotificationPermission() {
+        UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound]) { granted, error in
+            if let error {
+                Current.Log.error("Failed to request notification permission: \(error)")
+            } else if granted {
+                Current.Log.info("Notification permission granted for return reminders")
+            }
+        }
+    }
+
+    private func scheduleReturnNotification(timeout: TimeInterval) {
+        let content = UNMutableNotificationContent()
+        content.title = "Home Assistant"
+        content.body = "Time to return to your dashboard"
+        content.sound = .default
+        content.categoryIdentifier = "KIOSK_RETURN"
+
+        let trigger = UNTimeIntervalNotificationTrigger(timeInterval: timeout, repeats: false)
+        let request = UNNotificationRequest(
+            identifier: "kiosk.return.reminder",
+            content: content,
+            trigger: trigger
+        )
+
+        UNUserNotificationCenter.current().add(request) { error in
+            if let error {
+                Current.Log.error("Failed to schedule return notification: \(error)")
+            }
+        }
+    }
+
+    private func cancelReturnNotification() {
+        UNUserNotificationCenter.current().removePendingNotificationRequests(
+            withIdentifiers: ["kiosk.return.reminder"]
+        )
+    }
+}
+
+// MARK: - App Launcher Command Support
+
+extension AppLauncherManager {
+    /// Handle launch app command from HA notification
+    public func handleLaunchCommand(urlScheme: String) -> Bool {
+        // Find matching shortcut if exists
+        let shortcut = settings.appShortcuts.first { $0.urlScheme == urlScheme }
+        return launchApp(urlScheme: urlScheme, shortcut: shortcut)
+    }
+}
+
+// MARK: - Sensor Attributes
+
+extension AppLauncherManager {
+    /// Sensor state for HA reporting
+    public var sensorState: String {
+        appState.rawValue
+    }
+
+    /// Sensor attributes for HA reporting
+    public var sensorAttributes: [String: Any] {
+        var attrs: [String: Any] = [
+            "is_away": isAway,
+        ]
+
+        if let launchedApp {
+            attrs["launched_app"] = launchedApp.name
+            attrs["launched_scheme"] = launchedApp.urlScheme
+        }
+
+        if let launchTime {
+            attrs["launch_time"] = ISO8601DateFormatter().string(from: launchTime)
+            attrs["away_duration_seconds"] = Int(awayDuration ?? 0)
+        }
+
+        if returnTimeRemaining > 0 {
+            attrs["return_timeout_remaining"] = Int(returnTimeRemaining)
+        }
+
+        return attrs
+    }
+}