Fixed a critical issue with in-game chat.

GameServer/Game/Player/ChatMessageHelper.cs

@@ -0,0 +1,27 @@
+using System.Text.RegularExpressions;
+
+namespace MikuSB.GameServer.Game.Player;
+
+public static partial class ChatMessageHelper
+{
+    [GeneratedRegex(@"\s+")]
+    private static partial Regex MultiWhitespaceRegex();
+
+    public static uint BuildClientTimestamp()
+    {
+        return (uint)MikuSB.Util.Extensions.Extensions.GetUnixSec();
+    }
+
+    public static string NormalizeForClient(string? text)
+    {
+        if (string.IsNullOrWhiteSpace(text))
+            return string.Empty;
+
+        var normalized = text
+            .Replace("\r\n", " ")
+            .Replace('\r', ' ')
+            .Replace('\n', ' ');
+
+        return MultiWhitespaceRegex().Replace(normalized, " ").Trim();
+    }
+}