feature: Add missing properties to Guild and deprecate GuildEmbed (#1573)

* Add missing properties to Guild, related methods, and deprecate GuildEmbed endpoints

- Add missing guild properties: `discovery_splash`, `widget_enabled`, `widget_channel_id`, `rules_channel_id`, `max_presences`, `max_presences`, `max_members`, `public_updates_channel_id`, `max_video_channel_users`, `approximate_member_count`, `approximate_presence_count`
- Update guild properties: `embed_enabled`, `embed_channel_id`
- Add `GetGuildDiscoverySplashUrl` to `CDN`
- Add classes related to the guild widget
- Add `withCounts` parameter to `GetGuild(s)Async`
- Make GuildEmbed related methods obsolete with a message redirecting to widget ones

* Change xml docs and PremiumSubscriptionCount type

* Changed some xml docs

src/Discord.Net.Rest/API/Common/Guild.cs

@@ -13,6 +13,8 @@ namespace Discord.API
         public string Icon { get; set; }
         [JsonProperty("splash")]
         public string Splash { get; set; }
+        [JsonProperty("discovery_splash")]
+        public string DiscoverySplash { get; set; }
         [JsonProperty("owner_id")]
         public ulong OwnerId { get; set; }
         [JsonProperty("region")]
@@ -22,9 +24,9 @@ namespace Discord.API
         [JsonProperty("afk_timeout")]
         public int AFKTimeout { get; set; }
         [JsonProperty("embed_enabled")]
-        public bool EmbedEnabled { get; set; }
+        public Optional<bool> EmbedEnabled { get; set; }
         [JsonProperty("embed_channel_id")]
-        public ulong? EmbedChannelId { get; set; }
+        public Optional<ulong?> EmbedChannelId { get; set; }
         [JsonProperty("verification_level")]
         public VerificationLevel VerificationLevel { get; set; }
         [JsonProperty("default_message_notifications")]
@@ -43,6 +45,10 @@ namespace Discord.API
         public MfaLevel MfaLevel { get; set; }
         [JsonProperty("application_id")]
         public ulong? ApplicationId { get; set; }
+        [JsonProperty("widget_enabled")]
+        public Optional<bool> WidgetEnabled { get; set; }
+        [JsonProperty("widget_channel_id")]
+        public Optional<ulong?> WidgetChannelId { get; set; }
         [JsonProperty("system_channel_id")]
         public ulong? SystemChannelId { get; set; }
         [JsonProperty("premium_tier")]
@@ -56,9 +62,23 @@ namespace Discord.API
         // this value is inverted, flags set will turn OFF features
         [JsonProperty("system_channel_flags")]
         public SystemChannelMessageDeny SystemChannelFlags { get; set; }
+        [JsonProperty("rules_channel_id")]
+        public ulong? RulesChannelId { get; set; }
+        [JsonProperty("max_presences")]
+        public Optional<int?> MaxPresences { get; set; }
+        [JsonProperty("max_members")]
+        public Optional<int> MaxMembers { get; set; }
         [JsonProperty("premium_subscription_count")]
-        public int? PremiumSubscriptionCount { get; set; }
+        public Optional<int> PremiumSubscriptionCount { get; set; }
         [JsonProperty("preferred_locale")]
         public string PreferredLocale { get; set; }
+        [JsonProperty("public_updates_channel_id")]
+        public ulong? PublicUpdatesChannelId { get; set; }
+        [JsonProperty("max_video_channel_users")]
+        public Optional<int> MaxVideoChannelUsers { get; set; }
+        [JsonProperty("approximate_member_count")]
+        public Optional<int> ApproximateMemberCount { get; set; }
+        [JsonProperty("approximate_presence_count")]
+        public Optional<int> ApproximatePresenceCount { get; set; }
     }
 }

src/Discord.Net.Rest/API/Common/GuildWidget.cs

@@ -0,0 +1,13 @@
+#pragma warning disable CS1591
+using Newtonsoft.Json;
+
+namespace Discord.API
+{
+    internal class GuildWidget
+    {
+        [JsonProperty("enabled")]
+        public bool Enabled { get; set; }
+        [JsonProperty("channel_id")]
+        public ulong? ChannelId { get; set; }
+    }
+}

src/Discord.Net.Rest/API/Rest/ModifyGuildWidgetParams.cs

@@ -0,0 +1,14 @@
+#pragma warning disable CS1591
+using Newtonsoft.Json;
+
+namespace Discord.API.Rest
+{
+    [JsonObject(MemberSerialization = MemberSerialization.OptIn)]
+    internal class ModifyGuildWidgetParams
+    {        
+        [JsonProperty("enabled")]
+        public Optional<bool> Enabled { get; set; }
+        [JsonProperty("channel")]
+        public Optional<ulong?> ChannelId { get; set; }
+    }
+}