feat: redesign dashboard with Fluent KPI tiles, connection strip, and devices column

- Replace LCD-style readings with a 3×2 KPI tile grid (Fluent card surfaces, 52pt values)
- Add persistent top connection strip with horizontal chips + pump name badge
- Add elapsed test timer (DispatcherTimer, mm:ss) to Test Summary card
- Restyle Test Summary and Active Alarms with Fluent brushes/iconography
- Add Devices column (CAN / K-Line / Bench tiles) between KPI grid and test/alarms
  - Enumerates attached PCAN USB channels via PCAN_ATTACHED_CHANNELS API
  - Enumerates FTDI K-Line adapters via existing FtdiInterface helpers
  - Click to connect/disconnect; confirmation dialog when session active or test running
  - Hover tint: blue = will connect, red = will disconnect; Bench row is read-only stub
- Extend ICanService with SelectedChannel + EnumerateAttachedChannels()
- Expose IKwpService.ConnectedPort for active session device tracking
- Add DeviceRow button style with MultiDataTrigger hover colour logic
- Add 30+ new localization keys (ES + EN) for KPI labels, devices, confirmations

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ViewModels/MainViewModel.cs

@@ -5,6 +5,7 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Windows;
+using System.Windows.Threading;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using HC_APTBS.Models;
@@ -65,6 +66,14 @@ namespace HC_APTBS.ViewModels
 
         private CancellationTokenSource? _testCts;
 
+        // ── Test elapsed timer ────────────────────────────────────────────────────
+
+        /// <summary>Ticks every second while a test is running to update <see cref="TestElapsed"/>.</summary>
+        private DispatcherTimer? _testTimer;
+
+        /// <summary>UTC start time of the current test; used by the timer to compute elapsed duration.</summary>
+        private DateTime _testStartedUtc;
+
         // ── Unlock tracking ──────────────────────────────────────────────────────
 
         /// <summary>CTS for the currently running immobilizer unlock, if any.</summary>
@@ -139,9 +148,6 @@ namespace HC_APTBS.ViewModels
         /// <summary>Diagnostic Trouble Code list for the Pump page §3.b sub-section.</summary>
         public DtcListViewModel DtcList { get; }
 
-        /// <summary>Auth gate for the Pump page §3.d Adaptation sub-section.</summary>
-        public AuthGateViewModel AdaptationAuth { get; }
-
         // ── Page ViewModels (thin façades over the child VMs above) ───────────────
 
         /// <summary>Dashboard navigation page VM.</summary>
@@ -203,14 +209,12 @@ namespace HC_APTBS.ViewModels
             AngleDisplay       = new AngleDisplayViewModel(configService);
             DashboardAlarms    = new DashboardAlarmsViewModel(configService.Settings.Alarms);
             DtcList            = new DtcListViewModel(kwpService, localizationService, logger);
-            AdaptationAuth     = new AuthGateViewModel(configService, localizationService);
-
             // Page ViewModels are thin façades over the child VMs above; they hold a
             // reference back to this coordinator so page XAML can bind MainViewModel-owned
             // values via {Binding Root.X}.
-            DashboardPage = new DashboardPageViewModel(this);
+            DashboardPage = new DashboardPageViewModel(this, canService, kwpService);
             BenchPage     = new BenchPageViewModel(this, benchService, configService);
-            PumpPage      = new PumpPageViewModel(this, DtcList, AdaptationAuth);
+            PumpPage      = new PumpPageViewModel(this, DtcList);
             TestsPage     = new TestsPageViewModel(this, configService, localizationService);
             SettingsPage  = new SettingsPageViewModel(configService, localizationService);
             SettingsPage.SettingsSaved += OnSettingsSaved;
@@ -548,6 +552,9 @@ namespace HC_APTBS.ViewModels
         /// <summary>True when the current test results have been saved to a report.</summary>
         [ObservableProperty] private bool _isTestSaved = true;
 
+        /// <summary>Elapsed time since the current test started. Updated every second; retains last value when idle.</summary>
+        [ObservableProperty] private TimeSpan _testElapsed;
+
         // ── Commands: test ────────────────────────────────────────────────────────
 
         /// <summary>Starts the test sequence for the current pump.</summary>
@@ -806,6 +813,14 @@ namespace HC_APTBS.ViewModels
             {
                 IsTestRunning = true;
                 VerboseStatus = _loc.GetString("Test.Started");
+
+                _testStartedUtc = DateTime.UtcNow;
+                TestElapsed     = TimeSpan.Zero;
+                _testTimer      = new DispatcherTimer(
+                    TimeSpan.FromSeconds(1),
+                    DispatcherPriority.Normal,
+                    (_, _) => TestElapsed = DateTime.UtcNow - _testStartedUtc,
+                    App.Current.Dispatcher);
                 TestPanel.IsRunning = true;
                 TestPanel.ResetResults();
                 ResultDisplay.Clear();
@@ -817,6 +832,9 @@ namespace HC_APTBS.ViewModels
         private void OnTestFinished(bool interrupted, bool success)
             => App.Current.Dispatcher.Invoke(() =>
             {
+                _testTimer?.Stop();
+                _testTimer = null;
+
                 IsTestRunning   = false;
                 LastTestSuccess = !interrupted && success;
                 VerboseStatus   = interrupted ? _loc.GetString("Test.Stopped") : (success ? _loc.GetString("Common.Pass") : _loc.GetString("Common.Fail"));