Always On Top: Dedup the alwaysontop command id in window system menu (#45845)

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fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request
We picked a command id for always on top, although it has little
possibility, but may collide with other window system menu item, so
before inject, try to see if it persists, if yes, then we don't inject.


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## PR Checklist

- [ ] Closes: #xxx
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- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
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or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

<!-- Describe how you validated the behavior. Add automated tests
wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed
A window with the same id
<img width="1049" height="301" alt="image"
src="https://github.com/user-attachments/assets/ae0ba9b7-c46c-4cbf-8994-e0dc4e5c3527"
/>

You can see there is no always ontop overriding the test item

Normal window:
<img width="468" height="597" alt="image"
src="https://github.com/user-attachments/assets/2ba034a8-c41e-4233-9435-4323c8f1c7a4"
/>

src/modules/alwaysontop/AlwaysOnTop/AlwaysOnTop.cpp

@@ -22,6 +22,7 @@ namespace NonLocalizable
     const static wchar_t* TOOL_WINDOW_CLASS_NAME = L"AlwaysOnTopWindow";
     const static wchar_t* WINDOW_IS_PINNED_PROP = L"AlwaysOnTop_Pinned";
     constexpr UINT SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND = 0xEFE0;
+    constexpr ULONG_PTR SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND_OWNER_TAG = 0x414F5450;
     constexpr DWORD SYSTEM_EVENT_MENU_POPUP_START = 0x0006;
     constexpr DWORD SYSTEM_EVENT_MENU_POPUP_END = 0x0007;
 }
@@ -40,6 +41,29 @@ namespace
 
         hooks.clear();
     }
+
+    bool HasMenuCommand(HMENU menu, UINT commandId) noexcept
+    {
+        return menu && GetMenuState(menu, commandId, MF_BYCOMMAND) != static_cast<UINT>(-1);
+    }
+
+    bool IsAlwaysOnTopMenuCommand(HMENU menu) noexcept
+    {
+        if (!HasMenuCommand(menu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND))
+        {
+            return false;
+        }
+
+        MENUITEMINFOW menuItemInfo{};
+        menuItemInfo.cbSize = sizeof(menuItemInfo);
+        menuItemInfo.fMask = MIIM_DATA;
+
+        return GetMenuItemInfoW(menu,
+                                NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND,
+                                FALSE,
+                                &menuItemInfo) &&
+               menuItemInfo.dwItemData == NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND_OWNER_TAG;
+    }
 }
 
 bool isExcluded(HWND window)
@@ -503,7 +527,7 @@ void AlwaysOnTop::UpdateSystemMenuItem(HWND window) const noexcept
 
     if (!AlwaysOnTopSettings::settings().showInSystemMenu)
     {
-        if (GetMenuState(systemMenu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND, MF_BYCOMMAND) != static_cast<UINT>(-1))
+        if (IsAlwaysOnTopMenuCommand(systemMenu))
         {
             RemoveMenu(systemMenu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND, MF_BYCOMMAND);
         }
@@ -513,20 +537,26 @@ void AlwaysOnTop::UpdateSystemMenuItem(HWND window) const noexcept
     auto text = GET_RESOURCE_STRING(IDS_SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP);
     MENUITEMINFOW menuItemInfo{};
     menuItemInfo.cbSize = sizeof(menuItemInfo);
-    menuItemInfo.fMask = MIIM_ID | MIIM_STATE | MIIM_STRING;
+    menuItemInfo.fMask = MIIM_ID | MIIM_STATE | MIIM_STRING | MIIM_DATA;
     menuItemInfo.wID = NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND;
     menuItemInfo.fState = IsPinned(window) ? MFS_CHECKED : MFS_UNCHECKED;
     menuItemInfo.dwTypeData = text.data();
+    menuItemInfo.dwItemData = NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND_OWNER_TAG;
 
-    if (GetMenuState(systemMenu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND, MF_BYCOMMAND) == static_cast<UINT>(-1))
+    if (!HasMenuCommand(systemMenu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND))
     {
         InsertMenuItemW(systemMenu, SC_CLOSE, FALSE, &menuItemInfo);
     }
-    else
+    else if (IsAlwaysOnTopMenuCommand(systemMenu))
     {
         menuItemInfo.fMask = MIIM_STATE | MIIM_STRING;
         SetMenuItemInfoW(systemMenu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND, FALSE, &menuItemInfo);
     }
+    else
+    {
+        Logger::warn(L"Skipping Always On Top system menu command registration because ID 0x{:X} is already in use by another item.",
+                     NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND);
+    }
 }
 
 void AlwaysOnTop::UnpinAll()
@@ -652,8 +682,7 @@ void AlwaysOnTop::HandleWinHookEvent(WinHookEvent* data) noexcept
             }
 
             const auto systemMenu = GetSystemMenu(window, false);
-            return systemMenu &&
+            return systemMenu && IsAlwaysOnTopMenuCommand(systemMenu);
-                   GetMenuState(systemMenu, NonLocalizable::SYSTEM_MENU_TOGGLE_ALWAYS_ON_TOP_COMMAND, MF_BYCOMMAND) != static_cast<UINT>(-1);
         };
 
         HWND commandWindow = nullptr;