Add Node from node key

[aradng]

Headscale-admin has an add node feature which comes handy when not using oidc or pre-auth during new machine appends to tailnet. this with managing headscale config through headplane (similar to acl) can completely eliminate any admin intervention in cli.

also a configurable deploy tab for tailscale cli would be a nice to have :)

[tale]

Noted.

[tale]

Resolved in 0.3.2. See #22