More documentation - almost all Models done

https://github.com/oqtane/oqtane.framework/issues/1382
Should not contain any code changes, just docs

Oqtane.Shared/Models/ConnectionStringField.cs

@@ -1,13 +1,28 @@
 namespace Oqtane.Models
 {
+    /// <summary>
+    /// Helper class for input fields in the setup of the SQL connection
+    /// </summary>
     public class ConnectionStringField
     {
+        /// <summary>
+        /// Simple to understand field name / label
+        /// </summary>
         public string FriendlyName { get; set; }
 
+        /// <summary>
+        /// Instructions / help for the user
+        /// </summary>
         public string HelpText { get; set; }
 
+        /// <summary>
+        /// Property / Setting name which will be filled in by the user. Typically something like `Server`, `Port` etc.
+        /// </summary>
         public string Name { get; set; }
 
+        /// <summary>
+        /// Initial value used in the UI and probably later also the user input that was given.
+        /// </summary>
         public string Value { get; set; }
     }
 }