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>

Views/UserControls/DashboardDevicesView.xaml.cs

@@ -0,0 +1,16 @@
+using System.Windows.Controls;
+
+namespace HC_APTBS.Views.UserControls
+{
+    /// <summary>
+    /// Devices column for the Dashboard page — CAN, K-Line, and Bench device tiles.
+    /// DataContext is expected to be a <see cref="HC_APTBS.ViewModels.Pages.DashboardPageViewModel"/>.
+    /// </summary>
+    public partial class DashboardDevicesView : UserControl
+    {
+        public DashboardDevicesView()
+        {
+            InitializeComponent();
+        }
+    }
+}