Feature Request: URL Scheme for managing System protection

### Problem Description

The current Today Extension* (non-iOS 14 widget) has the following issue. When the AdGuard DNS is active, once a VPN (non-Personal VPN) is turned on and turned off, the real status of AdGuard DNS is inactive, but in the Today Extension, it is always active status. In order to active AdGuard DNS, I have to enter the APP (via Today Extension or APP icon).

*AdGuard currently has only one type of "widget", the official name is Today Extension. I am now using iOS 14.2.

### Step to reproduce the issue

#### Method 1
- Turn on AdGuard DNS (via Today Extension or AdGuard APP)
- Kill AdGuard in the background
- Turn on any VPN (not the personal VPN type, you can find the type of your VPN in Settings - VPN)
- Turn off the VPN
- Check the status of AdGuard DNS in Control Center and Today Extension

#### Method 2 (without killing AdGuard)
- Turn on AdGuard DNS (via Today Extension or AdGuard APP)
- Turn on any VPN (not the personal VPN type, you can find the type of your VPN in Settings - VPN)
- Turn off the VPN
- Never switch to AdGuard APP
- Check the status of AdGuard DNS in Control Center and Today Extension

### Proposed Solution

I saw that there is already a feature request for iOS widgets. In addition of that feature, it would be much better that you create two URL Schemes for DNS switche like
- adguard://dnson
- adguard://dnsoff

Besides, you can also add two URL Schemes for Safari content blocker switcher.

With the proposed URL Schemes, I can create a 1*1 icon to active it only with one click. In addition, I can create some automation in Shortcut APP.

### Additional Information

For anyone who need the current URL Schemes, here is the list:
- adguard:// Open AdGuard APP
- abp:// Open AdGuard APP (?)
- snds:// Set custom DNS settings