Conglomerate Hosts: optionally require an Owner-confirmed key fingerprint (second step after 0.15.0) #32

What

A possible second step after the Conglomerate Host route (#30, #31): let the broker mint a host token only for a key an Organization Owner has confirmed, instead of trusting every writer of the Deployment Repo's key ref.

Why it may matter later

In 0.15.0 the key document is trusted as far as the Deployment Repo is: whoever can write its ref can name a key and obtain members: read through it. The product owner accepted that on 2026-11-03, on the precondition that only Owners and the accounts a policy names in approved_writers write that repository (checked live by the broker), with Git history as the audit trail and, on paid plans, a ruleset that keeps that history. The product owner decided that no further verification is needed for now and that this would be a second step.

Shape, if it is taken up

• An Organization-level custom property on the Deployment Repo whose values only organization-level actors may edit (values_editable_by: org_actors), holding the host's public key (ed25519: + 43 characters fits the 75-character limit).
• The broker reads it live with its internal read token and mints only when it equals the key document's broker_key.
• Cost: one Owner step when an Organization joins a host and after every host rebuild; no broker deploy and no pull request. A product UI could make that step one click of the Owner's consent to join the Conglomerate.

Open before building

• Live proof that a repository admin who is not an Owner cannot set such a value, and that an installation token with contents: read + members: read can read it.

Not a blocker for #31.

Agent: environment a480495c-25e0-4e51-828b-1dbf1b77d62f · T3 thread 903f0db9-a125-40d4-b492-f40c2cb34529