refactor(ui): alert rows are two lines of text — the heading line was redundant

Creator: system messages are limited to two lines; the label above the message ('STEAM ID NOT
PRESENT', 'STREAM') was repeating what the row already said and pushing the stack past its budget.

AttentionAlert loses Label; rows render Text only. The licence row is now exactly:
    Steam ID Limit: 30fps
    Click for More Info
(60fps with a close control once owned). Rows are identified by Id internally, so nothing in the UI
depends on the removed text. Tests updated to assert position/text rather than the heading.

Controls/LeftPanel.xaml

@@ -81,12 +81,9 @@
                                               Width="14" Height="14" Stretch="Uniform" VerticalAlignment="Top"
                                               Margin="6,2,2,0" ToolTip="Standing indicator"
                                               Visibility="{Binding ShowsPin, Converter={StaticResource BoolToVis}}"/>
-                                        <StackPanel>
-                                            <TextBlock Text="{Binding Label}" Style="{StaticResource AppLogEntryText}"
-                                                       FontWeight="Bold" Foreground="{StaticResource Brush.Error}"/>
-                                            <TextBlock Text="{Binding Text}" Style="{StaticResource AppLogEntryText}"
-                                                       TextWrapping="Wrap" Margin="0,2,0,0"/>
-                                        </StackPanel>
+                                        <TextBlock Text="{Binding Text}" Style="{StaticResource AppLogEntryText}"
+                                                   TextWrapping="Wrap" VerticalAlignment="Center"
+                                                   Foreground="{StaticResource Brush.Error}"/>
                                     </DockPanel>
                                 </Border>
                             </DataTemplate>