Add manually verified keys

[jp-bennett]

I really like the idea of using a QR code to positively verify a node's identity, including the PKI public Key. This should inform the user that either a new entry is going to be added, or an entry is being updated. In the firmware, this nodeinfo needs to be special, never getting deleted. It also should have special protections against being updated, and never automatically.

[jp-bennett]

If we add key attestation, where attested keys are automatically updated, I would like manually verified keys to still not update automatically, but prompt the user.