Add Simplified Chinese localization and fix fullscreen menu bar trigger on notchless displays

[justinfjx]

Problem
On displays without a notch, when an app is in fullscreen mode, clicking at the top of the screen would incorrectly trigger Ice to show hidden menu bar items, even before the system menu bar had slid down.

Root Cause
The handleShowOnClick function was responding to clicks in the menu bar area without checking whether the system menu bar was actually visible on screen.

Solution
Added two checks in HIDEventManager.swift:

1. In handleShowOnClick: Before triggering the show action, check if a menu bar window is actually visible on screen using WindowInfo.menuBarWindow(). If no menu bar window exists on the current screen, the menu bar hasn't slid down yet, so we skip the action.
2. In isMouseInsideMenuBar: Added a check for isMenuBarHiddenBySystem in fullscreen mode on notchless displays as an additional safeguard.

Testing

1. Open a fullscreen app on an external display without a notch
2. Move mouse to top of screen but don't wait for system menu bar to slide down
3. Click at the top → Ice should NOT show hidden items
4. Wait for system menu bar to slide down, then click → Ice should respond normally