feat(payload-handler): wire DrawPopups + Integrations/ContextFooter/StringifyMessage

E2 fills the popup-dispatch layer of PayloadHandler:
- DrawPopups: switch-dispatch over payload types, with TODO(E3)/(E4)
  markers at the deferred Draw{Player,Item,Status,Uri}Popup call sites
- Integrations: invokes registered IPC integrations (LogWindow.Plugin.Ipc
  -> _ipc substitution per §4.2)
- ContextFooter: ScreenshotMode + HideChat checkboxes (Plugin.Config
  static-bridge substitutions per §4.2)
- StringifyMessage: pure helper, 1:1 from v1.5.6

Adds PopupSfx const (E1 polish — needed by E5's Click for
UIGlobals.PlaySoundEffect). Removes #pragma CS0169 for _popup since
DrawPopups now writes the field; the warning no longer triggers.

E3 will fill DrawPlayerPopup + FindCharacterForPayload; E4 the
Item/Status/Uri popups; E5 the Hover/Click bodies; E6 MoveTooltip.

HellionChat/PayloadHandler.cs

@@ -1,8 +1,15 @@
+using System.Linq;
 using Dalamud.Bindings.ImGui;
 using Dalamud.Game.Text.SeStringHandling;
+using Dalamud.Game.Text.SeStringHandling.Payloads;
+using Dalamud.Interface.ImGuiNotification;
+using Dalamud.Interface.Utility.Raii;
+using HellionChat.Code;
+using HellionChat.Resources;
 using HellionChat.Themes;
 using HellionChat.Ui.Components;
 using HellionChat.Ui.Windows;
+using HellionChat.Util;
 using Microsoft.Extensions.Logging;
 
 namespace HellionChat;
@@ -10,6 +17,7 @@ namespace HellionChat;
 internal sealed class PayloadHandler
 {
     private const string PopupId = "hellionchat-context-popup";
+    private const uint PopupSfx = 1;
 
     private readonly ThemeRegistry _themes;
     private readonly IpcManager _ipc;
@@ -24,9 +32,7 @@ internal sealed class PayloadHandler
     public uint HoverCounter;
     public uint LastHoverCounter;
 
-#pragma warning disable CS0169 // used in DrawPopups (E2)
     private (Chunk, Payload?)? _popup;
-#pragma warning restore CS0169
 
     public PayloadHandler(
         ThemeRegistry themes,
@@ -49,7 +55,7 @@ internal sealed class PayloadHandler
 
     internal void Draw()
     {
-        // TODO(E2): DrawPopups();
+        DrawPopups();
 
         if (HandleTooltips && ++HoverCounter - LastHoverCounter > 1)
         {
@@ -60,6 +66,157 @@ internal sealed class PayloadHandler
         }
     }
 
+    private void DrawPopups()
+    {
+        if (_popup == null)
+            return;
+
+        var (chunk, payload) = _popup.Value;
+
+        using var popup = ImRaii.Popup(PopupId);
+        if (!popup.Success)
+        {
+            _popup = null;
+            return;
+        }
+
+        using var id = ImRaii.PushId(PopupId);
+        var drawn = false;
+        switch (payload)
+        {
+            case PlayerPayload player:
+                // TODO(E3): DrawPlayerPopup(chunk, player);
+                drawn = true;
+                break;
+            case ItemPayload item:
+                // TODO(E4): DrawItemPopup(item);
+                drawn = true;
+                break;
+            case UriPayload uri:
+                // TODO(E4): DrawUriPopup(uri);
+                drawn = true;
+                break;
+            case StatusPayload status:
+                // TODO(E4): DrawStatusPopup(status);
+                drawn = true;
+                break;
+        }
+
+        ContextFooter(drawn, chunk);
+        Integrations(chunk, payload);
+    }
+
+    private void Integrations(Chunk chunk, Payload? payload)
+    {
+        var registered = _ipc.Registered;
+        if (registered.Count == 0)
+            return;
+
+        ImGui.Separator();
+
+        var contentId = chunk.Message?.ContentId ?? 0;
+        var sender =
+            chunk.Message?.Sender.Select(c => c.Link).FirstOrDefault(p => p is PlayerPayload)
+            as PlayerPayload;
+
+        using var menu = ImRaii.Menu(Language.Context_Integrations);
+        if (!menu.Success)
+            return;
+
+        var cursor = ImGui.GetCursorPos();
+        foreach (var integrationId in registered)
+        {
+            try
+            {
+                _ipc.Invoke(
+                    integrationId,
+                    sender,
+                    contentId,
+                    payload,
+                    chunk.Message?.SenderSource,
+                    chunk.Message?.ContentSource
+                );
+            }
+            catch (Exception ex)
+            {
+                _logger.LogError(ex, "Error executing integration");
+            }
+        }
+
+        if (cursor == ImGui.GetCursorPos())
+        {
+            using var pushedColor = ImRaii.PushColor(
+                ImGuiCol.Text,
+                ImGui.GetStyle().Colors[(int)ImGuiCol.TextDisabled]
+            );
+            ImGui.Text("No integrations available");
+        }
+    }
+
+    private void ContextFooter(bool didCustomContext, Chunk chunk)
+    {
+        ImRaii.MenuDisposable menu = default;
+        if (didCustomContext)
+        {
+            ImGui.Separator();
+
+            // Only place these menu items in a submenu if we've already drawn
+            // custom context menu items based on the payload.
+            //
+            // It makes it much more convenient in the majority of cases to
+            // copy the message content without having to open a submenu.
+            menu = ImRaii.Menu(Plugin.PluginName);
+            if (!menu.Success)
+                return;
+        }
+
+        ImGui.Checkbox(Language.Context_ScreenshotMode, ref Plugin.Config.ScreenshotMode);
+
+        if (ImGui.Selectable(Language.Context_HideChat))
+            Plugin.Config.HideChat = true;
+
+        if (chunk.Message is { } message)
+        {
+            if (ImGui.Selectable(Language.Context_Copy))
+            {
+                ImGui.SetClipboardText(StringifyMessage(message, true));
+                WrapperUtil.AddNotification(Language.Context_CopySuccess, NotificationType.Info);
+            }
+
+            // Only show a separate "Copy content" option if the message has
+            // Sender chunks, so it doesn't show for system messages.
+            if (message.Sender.Count > 0 && ImGui.Selectable(Language.Context_CopyContent))
+            {
+                ImGui.SetClipboardText(StringifyMessage(message));
+                WrapperUtil.AddNotification(
+                    Language.Context_CopyContentSuccess,
+                    NotificationType.Info
+                );
+            }
+
+            using var pushedColor = ImRaii.PushColor(
+                ImGuiCol.Text,
+                ImGui.GetStyle().Colors[(int)ImGuiCol.TextDisabled]
+            );
+            ImGui.TextUnformatted(message.Code.Type.Name());
+        }
+
+        menu.Dispose();
+    }
+
+    private static string StringifyMessage(Message? message, bool withSender = false)
+    {
+        if (message == null)
+            return string.Empty;
+
+        var chunks = withSender ? message.Sender.Concat(message.Content) : message.Content;
+        return chunks
+            .Where(chunk => chunk is TextChunk)
+            .Cast<TextChunk>()
+            .Select(text => text.Content)
+            .Aggregate(string.Concat);
+    }
+
     internal void Hover(Payload payload) { }
 
     internal unsafe void Click(Chunk chunk, Payload? payload, ImGuiMouseButton button) { }