PixelPaint: Add "Change Levels..." menu entry to Image menu

This adds the "Change Levels..." action to the Image menu in PixelPaint,
making it more discoverable alongside other image adjustment features.
The action was previously only accessible via the toolbar or keyboard
shortcut (Ctrl+L).

Fixes #26183

Author: Amogh-2404

Userland/Applications/PixelPaint/MainWidget.cpp

@@ -735,6 +735,18 @@ ErrorOr<void> MainWidget::initialize_menubar(GUI::Window& window)
             editor->did_complete_action("Crop Image to Content"sv);
         }));
 
+    m_image_menu->add_separator();
+
+    m_levels_dialog_action = GUI::Action::create(
+        "Change &Levels...", { Mod_Ctrl, Key_L }, g_icon_bag.levels, [&](auto&) {
+            auto* editor = current_image_editor();
+            VERIFY(editor);
+            auto dialog = PixelPaint::LevelsDialog::construct(&window, editor);
+            if (dialog->exec() != GUI::Dialog::ExecResult::OK)
+                dialog->revert_possible_changes();
+        });
+    m_image_menu->add_action(*m_levels_dialog_action);
+
     m_layer_menu = window.add_menu("&Layer"_string);
 
     m_layer_menu->on_visibility_change = [this](bool visible) {
@@ -1193,15 +1205,6 @@ ErrorOr<void> MainWidget::initialize_menubar(GUI::Window& window)
     }));
     help_menu->add_action(GUI::CommonActions::make_about_action("Pixel Paint"_string, GUI::Icon::default_icon("app-pixel-paint"sv), &window));
 
-    m_levels_dialog_action = GUI::Action::create(
-        "Change &Levels...", { Mod_Ctrl, Key_L }, g_icon_bag.levels, [&](auto&) {
-            auto* editor = current_image_editor();
-            VERIFY(editor);
-            auto dialog = PixelPaint::LevelsDialog::construct(&window, editor);
-            if (dialog->exec() != GUI::Dialog::ExecResult::OK)
-                dialog->revert_possible_changes();
-        });
-
     auto& toolbar = *find_descendant_of_type_named<GUI::Toolbar>("toolbar");
     toolbar.add_action(*m_new_image_action);
     toolbar.add_action(*m_open_image_action);