Quick settings tile

[ngregrichardson]

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Description

Adds a quick settings tile that allows you to quickly check the status and toggle the VPN (see https://github.com/orgs/fosrl/discussions/2955). I haven't worked in Kotlin before, so this was very much a "following the docs" situation. Any feedback is appreciated.

How to test?

1. Log into your pangolin instance
2. Swipe down and open the "Quick Settings" edit screen
3. Add the Pangolin quick settings tile (width of 2 to see the status)
4. Click the quick settings tile and see the VPN turn to "Connected" in the app
5. Disconnect in the app and see the quick settings tile turn to "Disconnected"

To Do

• I have not been able to test as low as Android 7.0 because my emulator does not have an updated cert store, so I cannot even log into my pangolin instance. Working on getting that set up now.

• The icon was the existing one, just reused, so it looks a bit small.

[ngregrichardson]

This works well on Android 7.0 still. Did realize in testing that that the post-install process is not great (before you've granted permissions to create a VPN)

[ngregrichardson]

I think this looks good from my end now, would love for someone to do some more testing and give feedback when possible!