feat: redesign bench calibration (factor/offset), add Ttank/P2 displays, fix sensor calibration

- Replace P1-P6 rational transfer function with factor/offset model for bench params
- Add explicit rx/tx direction flags in bench XML configuration
- Add T.Tank (BenchTemp) and P2 (AnalogSensor2) to temperature/pressure display
- Apply SensorConfiguration calibration to pressure channels, fix empty sensors.xml fallback
- Add live value labels to flowmeter charts
- Hide pump live values and PSG encoder standalone label
- Add K-Line connection state model, improve KWP service and status displays
- Restructure .claude/skills into subdirectory format

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

Views/UserControls/StatusDisplayView.xaml

@@ -44,8 +44,11 @@
                                    Width="12" Height="12"
                                    HorizontalAlignment="Center" VerticalAlignment="Center"
                                    ToolTip="{Binding Description}"
+                                   ToolTipService.InitialShowDelay="150"
+                                   ToolTipService.ShowDuration="30000"
                                    SnapsToDevicePixels="True"/>
                         <TextBlock Grid.Row="1" FontSize="8"
+                                   Text="{Binding Index}"
                                    HorizontalAlignment="Center" VerticalAlignment="Center"
                                    Foreground="DimGray"/>
                     </Grid>