Added a cli method to check the visibility of a window. (#301)

globals.d.ts

@@ -6,6 +6,7 @@ import { Options, Variable as VariableType } from 'types/variable';
 declare global {
     var globalMousePos: VariableType<number[]>;
     var useTheme: (filePath: string) => void;
+    var isWindowVisible: (windowName: string) => boolean;
     var globalWeatherVar: VariableType<Weather>;
     var options: Options;
     var removingNotifications: VariableType<boolean>;

globals/utilities.ts

@@ -0,0 +1,8 @@
+globalThis.isWindowVisible = (windowName: string): boolean => {
+    const appWindow = App.getWindow(windowName);
+
+    if (appWindow === undefined) {
+        return false;
+    }
+    return appWindow.visible;
+};

main.ts

@@ -1,6 +1,7 @@
 import 'lib/session';
 import 'scss/style';
 import 'globals/useTheme';
+import 'globals/utilities';
 import 'globals/mousePos';
 
 import { Bar } from 'modules/bar/Bar';