chore: implement full CSP support

[StoyanGoranov]

Implementing CSP compatibility features and fixes.

The unsafe-inline keyword is no longer required in the "style-src".

Fixes applied to EditorTemplates when global defer is used.

[mihaela-lukanova]

The editor templates of "Category" and "Country" fields in the "Demo_Overview_CSP" are not activated. Also, update the editors of the rets of the fields to be Kendo editors.

[StoyanGoranov]

The editor templates of "Category" and "Country" fields in the "Demo_Overview_CSP" are not activated. Also, update the editors of the rets of the fields to be Kendo editors.

Issue seems to be caused by global defer in Program.cs:
builder.Services.AddKendo(x => { x.DeferToScriptFiles = true; });

app.UseMiddleware<KendoDeferredScriptsMiddleware>();
since without these configurations the EditorTemplates are used correctly.

[StoyanGoranov]

To correctly initialize EditorTemplates in Grid deferred to a script file you need to:

1. Configure the editor ->
   @(Html.Kendo().Template().AddComponent(x => x.NumericTextBoxFor(m => m) .HtmlAttributes(new { style = "width:100%" }) .HtmlAttributes(new { title = Html.ViewContext.ViewData.TemplateInfo.GetFullHtmlFieldName("") })) )
2. Configure the column ->
   columns.Bound(p => p.UnitsInStock).Title("Units").Width(105).EditorTemplateComponentName("Number");

However, the Editor Templates are still not present in data-bound Components like DropDownLists.

[StoyanGoranov]

Columns that had lingering issue with displaying EditorTemplate were previously binding to a model subfield e.g Country.CoyntryNameLong instead of the field Country