fix(ViperQtProject): 主题切换同步应用 QPalette(修浅色勾选框缺失/深色框缺失)

ViperBTests/ViperQtProject/App/main.vp

@@ -432,9 +432,10 @@ def RestyleAll():
 
 
 def ApplyTheme(theme: int):
-    """切换深/浅主题并重刷内联样式"""
+    """切换深/浅主题：先设应用调色板（原生控件配色），再换 QSS 并重刷内联样式"""
     global cur_theme
     cur_theme = theme
+    vqt6.vqt6_qapplication_set_theme_palette(app_ptr, theme)
     if theme == 1:
         vqt6.vqt6_qwidget_set_stylesheet_utf8(central_ptr, light_qss)
     else:
@@ -478,6 +479,7 @@ def main() -> int:
 
     app = vqt6.QApplication(t.CPtr(0))
     app_ptr = t.CPtr(app._ptr)
+    vqt6.vqt6_qapplication_set_theme_palette(app_ptr, 0)
 
     # 主窗口（更宽更高）
     win = vqt6.QMainWindow()