revert(ui): remove the per-tab regex filter

HellionChat/Ui/SettingsTabs/Tabs.cs

@@ -1,10 +1,8 @@
 using Dalamud.Bindings.ImGui;
 using Dalamud.Game.ClientState.Objects.SubKinds;
 using Dalamud.Interface;
-using Dalamud.Interface.Colors;
 using Dalamud.Interface.Utility.Raii;
 using FFXIVClientStructs.FFXIV.Client.UI;
-using HellionChat._Helpers;
 using HellionChat.Code;
 using HellionChat.Resources;
 using HellionChat.Util;
@@ -240,25 +238,6 @@ internal sealed class Tabs : ISettingsTab
                     }
                 }
             }
-            // UI-8: optional regex filter for this tab.
-            var regexBuffer = tab.MessageRegex ?? string.Empty;
-            if (ImGui.InputText($"{HellionStrings.Settings_Tabs_MessageRegex_Name}##regex-{i}", ref regexBuffer, 256))
-                tab.MessageRegex = string.IsNullOrEmpty(regexBuffer) ? null : regexBuffer;
-            ImGuiUtil.HelpMarker(HellionStrings.Settings_Tabs_MessageRegex_Description);
-
-            // Validity feedback: the settings window is not a hot path, so a
-            // per-frame Compile is fine. An invalid pattern shows a red line and
-            // the tab behaves as if no regex were set.
-            if (!string.IsNullOrEmpty(tab.MessageRegex))
-            {
-                var (_, regexError) = RegexRouteMatcher.Compile(tab.MessageRegex);
-                if (regexError is not null)
-                    ImGui.TextColored(
-                        ImGuiColors.DalamudRed,
-                        string.Format(HellionStrings.Settings_Tabs_MessageRegex_Invalid, regexError)
-                    );
-            }
-
             ImGui.Checkbox(Language.Options_Tabs_PopOut, ref tab.PopOut);
             if (tab.PopOut)
             {