refactor(plugin): centralise slash-command registration for lazy-window readiness (v1.4.9 R1 stage 1)

Pull the four user-triggered slash-commands (/hellion, /hellionView,
/hellionDebugger, /hellionSeString) plus the two Plugin-Manager
UiBuilder hooks (OpenConfigUi, OpenMainUi) out of their window
constructors and into a central Plugin.SetupCommands method so they
work before their target window has been opened the first time. A
matching TearDownCommands runs as the first CaptureFailure inside the
framework-thread teardown lambda. /hellion and /hellionSeString stay
under the same #if DEBUG guard SeStringDebugger had before. The four
window classes keep their public Dispose method signatures so the
existing Plugin.DisposeAsync method-group binding still resolves —
the bodies are now empty pointers to TearDownCommands. The pre-v1.4.9
`OpenMainUi` body that flipped SettingsWindow.IsOpen and the three
private Toggle(string, string) method-group wrappers are gone since
the central handlers call SettingsWindow.Toggle() / DbViewer.Toggle()
etc. directly.

The properties stay eager in stage 1 — the lazy-init switch lands in
stage 2 with the matching `_lazyWindowLock` guard around AddWindow
and RemoveAllWindows. Doing it in two commits keeps the slash-command
correctness verifiable on its own.

Smoke (release build): /hellion, /hellionView, /hellionDebugger,
/clearhellion plus Plugin-Manager Settings and Open buttons all
toggle their target window. /hellionSeString remains DEBUG-only as
before.

HellionChat/Plugin.cs

@@ -289,6 +289,12 @@ public sealed class Plugin : IAsyncDalamudPlugin
 
             cancellationToken.ThrowIfCancellationRequested();
 
+            // Populate the command dictionary + UiBuilder hooks BEFORE
+            // Commands.Initialise() walks the dictionary and registers each
+            // entry with Dalamud's CommandManager (Commands.cs:15-28). Adding
+            // wrappers after Initialise() would leak them — they'd live in
+            // the dictionary but never reach Dalamud.
+            SetupCommands();
             Commands.Initialise();
 
             // Daily retention sweep — fire-and-forget, skips when disabled
@@ -424,7 +430,6 @@ public sealed class Plugin : IAsyncDalamudPlugin
             Framework.Update += FrameworkUpdate;
             Interface.UiBuilder.Draw += Draw;
             Interface.LanguageChanged += LanguageChanged;
-            Interface.UiBuilder.OpenMainUi += OpenMainUi;
         }
         catch
         {
@@ -455,7 +460,6 @@ public sealed class Plugin : IAsyncDalamudPlugin
         Exception? failure = null;
 
         // Unsubscribe hooks first — mirrors the hooks-last subscribe order in LoadAsync.
-        failure = CaptureFailure(failure, () => Interface.UiBuilder.OpenMainUi -= OpenMainUi);
         failure = CaptureFailure(failure, () => Interface.LanguageChanged -= LanguageChanged);
         failure = CaptureFailure(failure, () => Interface.UiBuilder.Draw -= Draw);
         failure = CaptureFailure(failure, () => Framework.Update -= FrameworkUpdate);
@@ -505,6 +509,11 @@ public sealed class Plugin : IAsyncDalamudPlugin
             await Framework
                 .RunOnFrameworkThread(() =>
                 {
+                    // TearDown slash-commands + UiBuilder hooks before windows
+                    // tear down. Slash-commands holding handlers that reach
+                    // the windows would otherwise see a half-torn Plugin.
+                    failure = CaptureFailure(failure, TearDownCommands);
+
                     failure = CaptureFailure(
                         failure,
                         () => GameFunctions.GameFunctions.SetChatInteractable(true)
@@ -683,11 +692,80 @@ public sealed class Plugin : IAsyncDalamudPlugin
         }
     }
 
-    private void OpenMainUi()
+    // Central slash-command + UiBuilder.OpenConfigUi/OpenMainUi subscribe so
+    // the four lazy windows (Settings, DbViewer, SeStringDebugger, Debugger)
+    // have working entry points before they're constructed.
+    private void SetupCommands()
     {
-        SettingsWindow.IsOpen = !SettingsWindow.IsOpen;
+        // ChatLogWindow.cs:128 already registers /hellion (ToggleChat). The
+        // description-arg here keeps the Dalamud help list populated.
+        Commands.Register("/hellion", "Perform various actions with Hellion Chat.").Execute +=
+            OnHellionSettingsCommand;
+        Commands
+            .Register(
+                "/hellionView",
+                "Get access to your message history, with simple filter options.",
+                true
+            )
+            .Execute += OnHellionViewCommand;
+        Commands.Register("/hellionDebugger", showInHelp: false).Execute +=
+            OnHellionDebuggerCommand;
+#if DEBUG
+        // SeStringDebugger.cs lives under #if DEBUG too; keep this out of release builds.
+        Commands.Register("/hellionSeString", showInHelp: false).Execute +=
+            OnHellionSeStringCommand;
+#endif
+
+        // Plugin-Manager "Settings" button. Was in Settings.cs:67 pre-v1.4.9.
+        Interface.UiBuilder.OpenConfigUi += OnOpenConfigUi;
+
+        // Plugin-Manager "Open" button. Was in Plugin.cs LoadAsync pre-v1.4.9
+        // (separate OpenMainUi handler that flipped SettingsWindow.IsOpen).
+        Interface.UiBuilder.OpenMainUi += OnOpenMainUi;
     }
 
+    private void TearDownCommands()
+    {
+        Interface.UiBuilder.OpenMainUi -= OnOpenMainUi;
+        Interface.UiBuilder.OpenConfigUi -= OnOpenConfigUi;
+
+        Commands.Register("/hellion", "Perform various actions with Hellion Chat.").Execute -=
+            OnHellionSettingsCommand;
+        Commands
+            .Register(
+                "/hellionView",
+                "Get access to your message history, with simple filter options.",
+                true
+            )
+            .Execute -= OnHellionViewCommand;
+        Commands.Register("/hellionDebugger", showInHelp: false).Execute -=
+            OnHellionDebuggerCommand;
+#if DEBUG
+        Commands.Register("/hellionSeString", showInHelp: false).Execute -=
+            OnHellionSeStringCommand;
+#endif
+    }
+
+    private void OnHellionSettingsCommand(string command, string arguments)
+    {
+        // /hellion with args is intentionally a no-op (matches pre-v1.4.9
+        // Settings.cs:76-80 behaviour).
+        if (string.IsNullOrWhiteSpace(arguments))
+            SettingsWindow.Toggle();
+    }
+
+    private void OnOpenConfigUi() => SettingsWindow.Toggle();
+
+    private void OnOpenMainUi() => SettingsWindow.Toggle();
+
+    private void OnHellionViewCommand(string _, string __) => DbViewer.Toggle();
+
+    private void OnHellionDebuggerCommand(string _, string __) => DebuggerWindow.Toggle();
+
+#if DEBUG
+    private void OnHellionSeStringCommand(string _, string __) => SeStringDebugger.Toggle();
+#endif
+
     private void RunRetentionSweepIfDue()
     {
         if (!Config.RetentionEnabled)

HellionChat/Ui/DbViewer.cs

@@ -93,29 +93,13 @@ public class DbViewer : Window
 
         RespectCloseHotkey = false;
         DisableWindowSounds = true;
-
-        Plugin
-            .Commands.Register(
-                "/hellionView",
-                "Get access to your message history, with simple filter options.",
-                true
-            )
-            .Execute += Toggle;
     }
 
     public void Dispose()
     {
-        Plugin
-            .Commands.Register(
-                "/hellionView",
-                "Get access to your message history, with simple filter options.",
-                true
-            )
-            .Execute -= Toggle;
+        // Slash-command tear-down moved to Plugin.TearDownCommands.
     }
 
-    private void Toggle(string _, string __) => Toggle();
-
     public override void Draw()
     {
         var totalPages = (int)Math.Ceiling((double)Count / RowPerPage);

HellionChat/Ui/Debugger.cs

@@ -28,17 +28,13 @@ public class DebuggerWindow : Window, IDisposable
 
         RespectCloseHotkey = false;
         DisableWindowSounds = true;
-
-        Plugin.Commands.Register("/hellionDebugger", showInHelp: false).Execute += Toggle;
     }
 
     public void Dispose()
     {
-        Plugin.Commands.Register("/hellionDebugger", showInHelp: false).Execute -= Toggle;
+        // Slash-command tear-down moved to Plugin.TearDownCommands.
     }
 
-    private void Toggle(string _, string __) => Toggle();
-
     public override unsafe void Draw()
     {
         var agent = (nint)AgentItemDetail.Instance();

HellionChat/Ui/SeStringDebugger.cs

@@ -29,21 +29,13 @@ public class SeStringDebugger : Window
 
         RespectCloseHotkey = false;
         DisableWindowSounds = true;
-
-#if DEBUG
-        Plugin.Commands.Register("/hellionSeString", showInHelp: false).Execute += Toggle;
-#endif
     }
 
     public void Dispose()
     {
-#if DEBUG
-        Plugin.Commands.Register("/hellionSeString", showInHelp: false).Execute -= Toggle;
-#endif
+        // Slash-command tear-down moved to Plugin.TearDownCommands.
     }
 
-    private void Toggle(string _, string __) => Toggle();
-
     public override void Draw()
     {
         if (Plugin.MessageManager.LastMessage.Sender == null)

HellionChat/Ui/Settings.cs

@@ -60,23 +60,11 @@ public sealed class SettingsWindow : Dalamud.Interface.Windowing.Window
         DisableWindowSounds = true;
 
         Initialise();
-
-        Plugin
-            .Commands.Register("/hellion", "Perform various actions with Hellion Chat.")
-            .Execute += Command;
-        Plugin.Interface.UiBuilder.OpenConfigUi += Toggle;
     }
 
     public void Dispose()
     {
-        Plugin.Interface.UiBuilder.OpenConfigUi -= Toggle;
-        Plugin.Commands.Register("/hellion").Execute -= Command;
-    }
-
-    private void Command(string command, string args)
-    {
-        if (string.IsNullOrWhiteSpace(args))
-            Toggle();
+        // Slash-command + OpenConfigUi tear-down moved to Plugin.TearDownCommands.
     }
 
     private void Initialise()