dev.knotless.addAgent

Names the account among the agents of the repository's dev.knotless.repo record, as `knotless agent add` does: accounts, such as a coding agent, whose pulls its runners check as they move, as code no one vouches for. Its owner can, logged in to this appview's web pages: the appview writes with the session it keeps for that account, which the pages' session cookie names. For an organization's repository, so can an admin who joined it, logged in to the pages or with a service token from their own PDS for this method: the appview's gateway, which the organization delegated its writes to, writes as the organization. Answers with the agents it names after.