feat(configmanager): add runtime config validation using Infrastructure validators

Enable ConfigManager to validate runtime configuration (SecureStore secrets,
connection strings, LDAP) using the same validators as the Host application.
Adds AddInfrastructureValidators() extension for shared validator registration.

NEW/src/Utils/JdeScoping.ConfigManager/Views/MainWindow.axaml

@@ -93,6 +93,7 @@
             <MenuItem Header="_Tools">
                 <MenuItem Header="_Validate All" Command="{Binding ValidateCommand}" InputGesture="F5"/>
                 <MenuItem Header="_Test Connection" Command="{Binding TestConnectionCommand}" InputGesture="F6"/>
+                <MenuItem Header="Validate _Runtime Config" Command="{Binding ValidateRuntimeConfigCommand}" InputGesture="F7"/>
                 <Separator/>
                 <MenuItem Header="View _Backups..."/>
             </MenuItem>
@@ -154,6 +155,8 @@
                 <Border Width="1" Height="20" Background="#2D3540" Margin="4,0"/>
                 <Button Content="Test" Command="{Binding TestConnectionCommand}" Classes="toolbar"/>
                 <Button Content="Validate" Command="{Binding ValidateCommand}" Classes="toolbar"/>
+                <Button Content="Validate Runtime" Command="{Binding ValidateRuntimeConfigCommand}"
+                        ToolTip.Tip="Validate SecureStore, Connection Strings, LDAP" Classes="toolbar"/>
                 <Border Width="1" Height="20" Background="#2D3540" Margin="4,0"/>
                 <Button Content="+ Pipeline" Command="{Binding AddPipelineCommand}" ToolTip.Tip="Add Pipeline" Classes="toolbar"/>
                 <Border Width="1" Height="20" Background="#2D3540" Margin="4,0"/>