fix(settings): stop drawing the same privacy options in two tabs

Three settings were rendered in two places at once, and the third is the one
that matters: the entire 89-entry channel grid existed twice. ChatTab's
"Channel filter" section and DataPrivacyTab's "Privacy filter" section wrote
the same HashSet through near-identical code, differing only in the ImGui id
suffix. Whichever one the user found first, the other silently showed the same
state.

ChatTab's section is gone entirely. DataPrivacyTab is a proper superset of it
-- it additionally carries PrivacyPersistUnknownChannels -- so nothing is lost.
PrintChangelog keeps only its General entry, where it belongs: it is start-up
behaviour, not privacy.

The lock-ordering comment moved before the deletion. DataPrivacyTab's version
was "see ChatTab for the ordering", a cross-reference to the file being
removed; the actual reasoning only existed in ChatTab.

HellionChat/Ui/Components/Settings/Tabs/ChatTab.cs

@@ -47,16 +47,6 @@ internal sealed class ChatTab
             DrawNameFormCombo();
         }
 
-        if (ImGui.CollapsingHeader("Channel filter"))
-        {
-            DrawToggle(
-                "Privacy filter enabled",
-                () => Plugin.Config.PrivacyFilterEnabled,
-                v => Plugin.Config.PrivacyFilterEnabled = v
-            );
-            DrawPrivacyPersistChannels();
-        }
-
         if (ImGui.CollapsingHeader("Command help"))
         {
             DrawCommandHelpSideCombo();
@@ -73,35 +63,6 @@ internal sealed class ChatTab
         }
     }
 
-    private void DrawPrivacyPersistChannels()
-    {
-        // Enum.GetValues gives a stable order; HashSet membership is the source
-        // of truth, so we toggle via Add/Remove instead of mutating a copy.
-        ImGui.TextUnformatted("Persist channels:");
-        foreach (var ct in Enum.GetValues<ChatType>())
-        {
-            var label = ct.ToString();
-            var present = Plugin.Config.PrivacyPersistChannels.Contains(ct);
-            if (ImGui.Checkbox($"{label}##persist-{label}", ref present))
-            {
-                // Lock closes before SaveConfig: taking ConfigMapsLock across a save
-                // would invert the lock order (SaveConfig can reach TabsListLock).
-                lock (_plugin.ConfigMapsLock)
-                {
-                    if (present)
-                    {
-                        Plugin.Config.PrivacyPersistChannels.Add(ct);
-                    }
-                    else
-                    {
-                        Plugin.Config.PrivacyPersistChannels.Remove(ct);
-                    }
-                }
-                _plugin.SaveConfig();
-            }
-        }
-    }
-
     private void DrawCommandHelpSideCombo()
     {
         var current = Plugin.Config.CommandHelpSide;

HellionChat/Ui/Components/Settings/Tabs/DataPrivacyTab.cs

@@ -16,11 +16,6 @@ internal sealed class DataPrivacyTab
     {
         if (ImGui.CollapsingHeader("Logging", ImGuiTreeNodeFlags.DefaultOpen))
         {
-            DrawToggle(
-                "Print changelog on update",
-                () => Plugin.Config.PrintChangelog,
-                v => Plugin.Config.PrintChangelog = v
-            );
             DrawToggle(
                 "Enable retention sweep",
                 () => Plugin.Config.RetentionEnabled,
@@ -81,7 +76,8 @@ internal sealed class DataPrivacyTab
             var present = Plugin.Config.PrivacyPersistChannels.Contains(ct);
             if (ImGui.Checkbox($"{label}##privacy-persist-{label}", ref present))
             {
-                // Lock closes before the save below, see ChatTab for the ordering.
+                // Lock closes before SaveConfig: taking ConfigMapsLock across a save
+                // would invert the lock order (SaveConfig can reach TabsListLock).
                 lock (_plugin.ConfigMapsLock)
                 {
                     if (present)