Add a sticky notification for scanning status, and request for unrestricted background policy at first run

[CanglanXYA]

Above methods will improve users' experience when scanning is running at background.

[CanglanXYA]

（by the way the app's logo is the same as an old app called SelinuxModeChanger, I was confused at first sight）

[CanglanXYA]

Im also wondering if this app support multiuser scanning. Because it seems wont request root access, which means it maybe have no chance to check other user's data.

If you want to manage other user profile, I guess we need to get root access at first and use that power to kill process at another user 🤔