Rate limit ahelps (#29219)

* Make chat rate limits a general-purpose system.

Intending to use this with ahelps next.

* Rate limt ahelps

Fixes #28762

* Review comments

Content.Shared.Database/LogType.cs

@@ -96,5 +96,13 @@ public enum LogType
     ChatRateLimited = 87,
     AtmosTemperatureChanged = 88,
     DeviceNetwork = 89,
-    StoreRefund = 90
+    StoreRefund = 90,
+
+    /// <summary>
+    /// User was rate-limited for some spam action.
+    /// </summary>
+    /// <remarks>
+    /// This is a default value used by <c>PlayerRateLimitManager</c>, though users can use different log types.
+    /// </remarks>
+    RateLimited = 91,
 }