Add config so it is configurable whether to explicitly index each nested property (#14648)

* Added new configuration "Umbraco:CMS:Examine:ExplicitlyIndexEachNestedProperty" that can be used to avoid nested properties like block grid to index each property individually.

* Moved the setting "Umbraco:CMS:Examine:ExplicitlyIndexEachNestedProperty" to "Umbraco:CMS:Indexing:ExplicitlyIndexEachNestedProperty" to make it more future proof

* Added missing registration

* Fixed registration

* Small readability improvement

---------

Co-authored-by: Sven Geusens <sge@umbraco.dk>

src/Umbraco.Core/Configuration/Models/IndexingSettings.cs

@@ -0,0 +1,18 @@
+using System.ComponentModel;
+
+namespace Umbraco.Cms.Core.Configuration.Models;
+
+/// <summary>
+///     Typed configuration options for index creator settings.
+/// </summary>
+[UmbracoOptions(Constants.Configuration.ConfigIndexing)]
+public class IndexingSettings
+{
+    private const bool StaticExplicitlyIndexEachNestedProperty = true;
+
+    /// <summary>
+    /// Gets or sets a value for whether each nested property should have it's own indexed value. Requires a rebuild of indexes when changed.
+    /// </summary>
+    [DefaultValue(StaticExplicitlyIndexEachNestedProperty)]
+    public bool ExplicitlyIndexEachNestedProperty { get; set; } = StaticExplicitlyIndexEachNestedProperty;
+}