The required-domain assertion in hive-network.nix could not be reached:
`forge.<domain>` and `matrix.<domain>` are evaluated while the
assertion list is, so an unset domain threw `cannot coerce null to a
string` naming one of those options instead of printing the message
that says which option to set.
Both defaults now fall back to a name under the reserved `.invalid`
TLD, which the assertion refuses to let out the door.
Second slice of the swarm-global service consolidation, same shape as
the forge move: the operator-facing host options become
services.hyperhive.swarm.matrix.*, and one mkRenamedOptionModule on the
namespace carries the whole subtree (nested gui.* included), so there is
no leaf list to forget an entry from.
The rename lives in hive-matrix.nix, the module that declares the
options, so each service's migration stays independent of its siblings.
The per-agent hyperhive.matrix.{enable,url} and hyperhive.matrixAccounts
are a different namespace -- a client pointer at the service, not the
service -- and deliberately do not move.
Nix half of the 4th layer mara found (47535: core cannot assume matrix
is on localhost). Rust half (matrix.rs MATRIX_HTTP) NOT done.
Parked here rather than left dirty: she has redirected me to jobq as
prio 1, and uncommitted files migrate across a checkout.
