Move ChatSystem.Emotes to shared (#40866)

* move to shared

* entity effect to shared

* refactor: whitespaces+xml-doc typo fixups

* refactor: a little bit more of xml-doc typos fixups

---------

Co-authored-by: pa.pecherskij <pa.pecherskij@interfax.ru>

Content.Shared/Chat/EmotesEvents.cs

@@ -1,9 +1,49 @@
-using Content.Shared.Chat.Prototypes;
+using Content.Shared.Chat.Prototypes;
+using Content.Shared.Inventory;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Serialization;
 
 namespace Content.Shared.Chat;
 
+/// <summary>
+/// An event raised just before an emote is performed, providing systems with an opportunity to cancel the emote's performance.
+/// </summary>
+[ByRefEvent]
+public sealed class BeforeEmoteEvent(EntityUid source, EmotePrototype emote)
+    : CancellableEntityEventArgs, IInventoryRelayEvent
+{
+    public readonly EntityUid Source = source;
+    public readonly EmotePrototype Emote = emote;
+
+    /// <summary>
+    /// The equipment that is blocking emoting. Should only be non-null if the event was canceled.
+    /// </summary>
+    public EntityUid? Blocker = null;
+
+    public SlotFlags TargetSlots => SlotFlags.WITHOUT_POCKET;
+}
+
+/// <summary>
+/// Raised by the chat system when an entity made some emote.
+/// Use it to play sound, change sprite or something else.
+/// </summary>
+[ByRefEvent]
+public record struct EmoteEvent(EmotePrototype Emote)
+{
+    /// <summary>
+    /// The used emote.
+    /// </summary>
+    public EmotePrototype Emote = Emote;
+
+    /// <summary>
+    /// If this message has already been "handled" by a previous system.
+    /// </summary>
+    public bool Handled;
+}
+
+/// <summary>
+/// Sent by the client when requesting the server to play a specific emote selected from the emote radial menu.
+/// </summary>
 [Serializable, NetSerializable]
 public sealed class PlayEmoteMessage(ProtoId<EmotePrototype> protoId) : EntityEventArgs
 {