The BackendParams typed enum was a spec bug: it created a partial
inversion (trait inverted, params not), modeled the SSH channel as an
input when it is an output (the backend opens it in allocate()), and
created a dependency contradiction — SshChannelRef could not live in
alknet-ssh (alknet-tty would depend on it) nor in alknet-tty (would pull
in russh types) without violating the inversion ADR-053 establishes.
Replaced with an opaque serde_json::Map: the adapter passes the
negotiation frame's backend-specific fields through verbatim; each
backend deserializes its own strongly-typed params struct. alknet-tty
has zero knowledge of any backend's params shape. Added a resource_id()
default method to TtyBackend so the ownership check (ADR-050) is
backend-driven rather than the adapter hardcoding docker's container
field extraction. The inversion is now complete — both the trait and
the params are inverted; adding SSH (or any future backend) is purely
additive: zero changes to alknet-tty, zero changes to existing call
sites.
glm-5.2
b90d717ac2