Add Settings to web app (#125)

* Add support for opening settings dialog in the webapp

* Add tests for settings dialog

* Hide stand-alone app specific settings in web app

* Remove debug log

electron/preload/index.ts

@@ -25,6 +25,7 @@ contextBridge.exposeInMainWorld("heynote", {
         isWindows,
         isLinux,
     },
+    isWebApp: false,
 
     themeMode: themeMode,