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>

MainWindow.xaml

@@ -1,6 +1,7 @@
-<Window x:Class="HC_APTBS.MainWindow"
+<ui:FluentWindow x:Class="HC_APTBS.MainWindow"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:ui="http://schemas.lepo.co/wpfui/2022/xaml"
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:vm="clr-namespace:HC_APTBS.ViewModels"
@@ -13,13 +14,18 @@
         WindowState="Maximized"
         WindowStartupLocation="CenterScreen"
         FontFamily="Ebrima"
-        Background="#FFEDEDED"
         Closing="OnWindowClosing">
 
     <DockPanel>
 
+        <!-- ── WPF-UI custom title bar (replaces OS chrome) ──────────────────── -->
+        <ui:TitleBar DockPanel.Dock="Top"
+                     Title="{DynamicResource App.Title}"
+                     ShowMaximize="True"
+                     ShowMinimize="True"/>
+
         <!-- ── Persistent app header: pump identification + connection state ──── -->
-        <Border DockPanel.Dock="Top" Background="#FFEDEDED"
+        <Border DockPanel.Dock="Top" Background="Transparent"
                 BorderBrush="#999" BorderThickness="0,0,0,1" Visibility="Collapsed">
             <Grid Margin="4,2">
                 <Grid.ColumnDefinitions>
@@ -204,4 +210,4 @@
             </TabControl>
         </Grid>
     </DockPanel>
-</Window>
+</ui:FluentWindow>