Approve a device request under the signed-in account

Grant a machine a place under this account, on the credential it pinned.

The standing assertion, the node limit, the create-or-adopt and the compare-and-set are all one transaction inside :func:~nerdit_cloud.nodes.link.approve_device_request — approval is the browser consume of the NL- flow, relabelled (D-X16-O1), and it is the mint-equivalent path, so an account that may not mint may not enroll a machine by this door either (D-X16-O25).

The reported hostname is read here and passed down because it is the stem of the node's slug: it is the display half of the row, and the policy layer takes it as an argument rather than trusting it to be present.