docs: add XML documentation and ConfigManager implementation plans

Add comprehensive XML documentation (param/returns tags) across 132 source
files to improve IntelliSense and API discoverability. Include ConfigManager
design documents and implementation plans for phases 1-9.

NEW/src/JdeScoping.Client/Extensions/ViewModelMappingExtensions.cs

@@ -22,6 +22,7 @@ public static class ViewModelMappingExtensions
     /// <summary>
     /// Maps Core SearchViewModel to Client SearchViewModel.
     /// </summary>
+    /// <param name="vm">The Core SearchViewModel to map.</param>
     public static SearchViewModel ToClient(this CoreSearch vm) => new()
     {
         Id = vm.Id,
@@ -37,6 +38,7 @@ public static class ViewModelMappingExtensions
     /// <summary>
     /// Maps Client SearchViewModel to Core SearchViewModel.
     /// </summary>
+    /// <param name="vm">The Client SearchViewModel to map.</param>
     public static CoreSearch ToCore(this SearchViewModel vm)
     {
         ArgumentNullException.ThrowIfNull(vm);
@@ -58,6 +60,7 @@ public static class ViewModelMappingExtensions
     /// Maps Core SearchCriteria to Client SearchCriteriaViewModel.
     /// Core uses primitive lists; Client uses full view model objects.
     /// </summary>
+    /// <param name="criteria">The Core SearchCriteria to map.</param>
     public static SearchCriteriaViewModel ToClientCriteria(this SearchCriteria criteria)
     {
         var client = new SearchCriteriaViewModel
@@ -107,6 +110,7 @@ public static class ViewModelMappingExtensions
     /// Maps Client SearchCriteriaViewModel to Core SearchCriteria.
     /// Client uses full view model objects; Core uses primitive lists.
     /// </summary>
+    /// <param name="criteria">The Client SearchCriteriaViewModel to map.</param>
     public static SearchCriteria ToCoreCriteria(this SearchCriteriaViewModel criteria)
     {
         ArgumentNullException.ThrowIfNull(criteria);
@@ -131,6 +135,7 @@ public static class ViewModelMappingExtensions
     /// <summary>
     /// Maps Core JdeUserViewModel to Client OperatorViewModel.
     /// </summary>
+    /// <param name="vm">The Core JdeUserViewModel to map.</param>
     public static OperatorViewModel ToClientOperator(this CoreJdeUser vm) => new()
     {
         AddressNumber = vm.AddressNumber,
@@ -141,6 +146,7 @@ public static class ViewModelMappingExtensions
     /// <summary>
     /// Maps a collection of Core SearchViewModels to Client SearchViewModels.
     /// </summary>
+    /// <param name="list">The collection of Core SearchViewModels to map.</param>
     public static List<SearchViewModel> ToClientList(this IEnumerable<CoreSearch> list)
     {
         ArgumentNullException.ThrowIfNull(list);
@@ -150,6 +156,7 @@ public static class ViewModelMappingExtensions
     /// <summary>
     /// Maps a collection of Core JdeUserViewModels to Client OperatorViewModels.
     /// </summary>
+    /// <param name="list">The collection of Core JdeUserViewModels to map.</param>
     public static List<OperatorViewModel> ToClientOperatorList(this IEnumerable<CoreJdeUser> list)
     {
         ArgumentNullException.ThrowIfNull(list);