Support for WireGuard only peers

[Haxverse]

Why

Tailscale announced their support for integrated Mullvad exit nodes a while back. Being able to configure a similar setup via ionscale and independent Mullvad account(s) would be useful.

Description

I haven't looked deeply into the details, but it's my understanding that this is implemented via a "WireGuard only peer" feature, and then support in the Tailscale coordination server to synchronize these peers with Mullvad. I assume it would be possible for ionscale to allow manually configuring these peer types. The way I see it, you'd add one or multiple Mullvad account(s) to a tailnet, and the ionscale server adds the needed public node keys to the Mullvad api up to the limit of your added Mullvad accounts.

[unixfox]

Related: juanfont/headscale#1545

[github-actions]

This issue is stale because it has been open for 90 days with no activity.

[aniqueta]

Not stale.

[github-actions]

This issue is stale because it has been open for 90 days with no activity.

[Haxverse]

Not stale.

[github-actions]

This issue is stale because it has been open for 90 days with no activity.

[Victor239]

Not stale.

[unixfox]

I shared some very detailed debug data here and including some advanced explanations: juanfont/headscale#1545 (comment)

@jsiebens if you want to take a look at, I still have the tailscale account access for further debugging. Looking forward for such feature 😃