Supersedes 0032, which decided the right thing and described it wrongly.
The decision is unchanged: the account that installed the host owns the
mesh, and there is no user model.
What was wrong was inventing "a surface that delegates authentication"
for the board. It is a web application with a login, in the way every
web application has a login. That is a fact about an application, not a
property of the mesh.
The cost was not cosmetic. It made the identity module look like part of
the mesh's authority — something the mesh depends on to know who anybody
is — when the mesh knows nothing about people at all and one of the
applications running on it happens to have a login.
Keeps the line that is worth writing down, and states it more plainly:
signing in to an application must not become authority over the mesh.
Today it cannot, because the board reads and does not act. The moment it
can assign a module, whoever it lets in has mesh authority — and it
would arrive as a feature rather than as a decision. So a surface that
can change the mesh is a change to who owns the mesh, and is taken as
one. Not forbidden; just not something that turns up in a pull request
titled "add assign button".
