[Feature] AutoMod support (#2578)

* initial implementation

* update models

* somewhat working auto mod action executed event

* made some properties optional

* comments, rest entity, guild methods

* add placeholder methods

* started working on rule cache

* working events

* started working on rule builder

* working state

* fix null issue

* commentsssss

* public automod rules collection in a socketgulild

* forgot nullability

* update limits

* add Download func to cacheable user

* Apply suggestions from code review

* Update src/Discord.Net.Rest/DiscordRestApiClient.cs

* missing xml doc

* reworkkkk

* fix the `;` lol

---------

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

src/Discord.Net.WebSocket/API/Gateway/AutoModActionExecutedEvent.cs

@@ -0,0 +1,38 @@
+using Newtonsoft.Json;
+namespace Discord.API.Gateway;
+
+internal class AutoModActionExecutedEvent
+{
+    [JsonProperty("guild_id")]
+    public ulong GuildId { get; set; }
+
+    [JsonProperty("action")]
+    public Discord.API.AutoModAction Action { get; set; }
+
+    [JsonProperty("rule_id")]
+    public ulong RuleId { get; set; }
+
+    [JsonProperty("rule_trigger_type")]
+    public AutoModTriggerType TriggerType { get; set; }
+
+    [JsonProperty("user_id")]
+    public ulong UserId { get; set; }
+
+    [JsonProperty("channel_id")]
+    public Optional<ulong> ChannelId { get; set; }
+
+    [JsonProperty("message_id")]
+    public Optional<ulong> MessageId { get; set; }
+
+    [JsonProperty("alert_system_message_id")]
+    public Optional<ulong> AlertSystemMessageId { get; set; }
+
+    [JsonProperty("content")]
+    public string Content { get; set; }
+
+    [JsonProperty("matched_keyword")]
+    public Optional<string> MatchedKeyword { get; set; }
+
+    [JsonProperty("matched_content")]
+    public Optional<string> MatchedContent { get; set; }
+}