[ifcbrk] feature: Implement Client Status Support (#1247)

* Implement Client Status Support

Adds support for using the client_status as sent as part of the Presence model. This value can be used to determine if a user is active on the native desktop app, the mobile app, or the website.

* lint: whitespace in IPresence

* Remove breaking change to IPresence interface with a note for 2.1

* update comment to not reference 2.1

* re-add interface break to IPresence

* add example payload for client_status

* use inline declaration for Enum.TryParse

src/Discord.Net.Core/Entities/Users/ClientType.cs

@@ -0,0 +1,21 @@
+namespace Discord
+{
+    /// <summary>
+    ///     Defines the types of clients a user can be active on.
+    /// </summary>
+    public enum ClientType
+    {
+        /// <summary>
+        ///     The user is active using the mobile application.
+        /// </summary>
+        Mobile,
+        /// <summary>
+        ///     The user is active using the desktop application.
+        /// </summary>
+        Desktop,
+        /// <summary>
+        ///     The user is active using the web application.
+        /// </summary>
+        Web
+    }
+}

src/Discord.Net.Core/Entities/Users/IPresence.cs

@@ -1,3 +1,5 @@
+using System.Collections.Immutable;
+
 namespace Discord
 {
     /// <summary>
@@ -13,5 +15,9 @@ namespace Discord
         ///     Gets the current status of this user.
         /// </summary>
         UserStatus Status { get; }
+        /// <summary>
+        ///     Gets the set of clients where this user is currently active.
+        /// </summary>
+        IImmutableSet<ClientType> ActiveClients { get; }
     }
 }