[Improvement] - Open browser for external OIDC

# Issue

Currently when a user logs in from the desktop app, the user is redirected within the app to the OIDC provider. This works, but passkeys are not supported in the dekstop app (or are currently not working).

# Solution

Instead of redirecting the user to the OIDC url within the app, open the default browser with a sign in link that redirects to the OIDC provider and when the user successfully authenticated open the huly desktop app with a callback code to sign in to the desktop app. This is fairly easy to implement with [Electron protocol](https://www.electronjs.org/docs/latest/api/protocol) and users will never have the problem that new browser api's are not supported by electron.

# Example app

This example app shows the concept: https://github.com/casdoor/casdoor-electron-example