[Feature] RespondWithModal() which accepts an IModal instance as template (#2564)

* introduce overload for responding to an interaction with an instatiated IModal obj

* add inline docs to ModalInfo.PropertyInfo

* Apply suggestions from code review

Co-authored-by: Casmir <68127614+csmir@users.noreply.github.com>

---------

Co-authored-by: Casmir <68127614+csmir@users.noreply.github.com>

src/Discord.Net.Interactions/Builders/Modals/Inputs/IInputComponentBuilder.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Reflection;
 
 namespace Discord.Interactions.Builders
 {
@@ -38,6 +39,11 @@ namespace Discord.Interactions.Builders
         /// </summary>
         Type Type { get; }
 
+        /// <summary>
+        ///     Get the <see cref="PropertyInfo"/> of this component's property.
+        /// </summary>
+        PropertyInfo PropertyInfo { get; }
+
         /// <summary>
         ///     Get the <see cref="ComponentTypeConverter"/> assigned to this input.
         /// </summary>

src/Discord.Net.Interactions/Builders/Modals/Inputs/InputComponentBuilder.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Reflection;
 
 namespace Discord.Interactions.Builders
 {
@@ -33,6 +34,9 @@ namespace Discord.Interactions.Builders
         /// <inheritdoc/>
         public Type Type { get; private set; }
 
+        /// <inheritdoc/>
+        public PropertyInfo PropertyInfo { get; internal set; }
+
         /// <inheritdoc/>
         public ComponentTypeConverter TypeConverter { get; private set; }
 

src/Discord.Net.Interactions/Builders/Modals/ModalBuilder.cs

@@ -37,6 +37,8 @@ namespace Discord.Interactions.Builders
             if (!typeof(IModal).IsAssignableFrom(type))
                 throw new ArgumentException($"Must be an implementation of {nameof(IModal)}", nameof(type));
 
+            Type = type;
+
             _interactionService = interactionService;
             _components = new();
         }