fix: disable text color hard to read

针对QPalette::Text的disable状态在暗色主题下在dialog透明模糊时，如果后面有白色背景的应用几乎看不清文字的修复。修改方法是将原来混合颜色改成降低透明度，disable时透明度未原来的40%(来自设计的建议)

Log: 修复控制中心在白色背景下，开启屏幕的第一个屏幕名称看不清的问题
Bug: https://pms.uniontech.com/zentao/bug-view-53017.html
Change-Id: Id6ce0d4bacaa7755b5d108c484d7707760bd4a72

src/dguiapplicationhelper.cpp

@@ -565,6 +565,12 @@ static void generatePaletteColor_helper(DPalette &base, M role, DGuiApplicationH
     const QColor &color = base.color(QPalette::Normal, role);
     base.setColor(QPalette::Disabled, role, DGuiApplicationHelper::blendColor(color, disable_mask_color));
 
+    QPalette::ColorRole qr = static_cast<QPalette::ColorRole>(role);
+    if (qr == QPalette::Text) {
+        // disable text color olny -60% alpha
+        base.setColor(QPalette::Disabled, role, DGuiApplicationHelper::adjustColor(color, 0, 0, 0, 0, 0, 0, -60));
+    }
+
     if (DGuiApplicationHelperPrivate::useInactiveColor)
         base.setColor(QPalette::Inactive, role, DGuiApplicationHelper::blendColor(color, inactive_mask_color));
     else