Rename `cargo xtask provisioning-reconciler-demo` to `cargo xtask demo`
(CLI dispatch, help, child re-exec argv, launch spec strings, module dir
xtask/src/provisioning_demo -> xtask/src/demo).
Add iteration-1 data-plane edges, established from Fleet Control:
- Fleet Control "edge" button -> POST /control/edge (new
ControlCommand::EstablishEdge) -> supervisor actor resolves the node's
advertised EndpointAddr (stashed in NodeRuntime by AnnounceActor) and
provisions a real outbound EdgeRuntime (arena ring lease, recorder
WorkerPort, EDGE_ALPN send pump) in a new edge pump thread.
- Node gains EDGE_ALPN, an actor bridge decoding EdgeProvision gossip,
and a NodeEdgeAgent that provisions its (single) inbound edge, polls
it, mirrors observations onto the node.edge telemetry channel
(render-only), and answers EdgeAck gossip which terminates the
supervisor's provision retries. Node teardown replaces its inbound on
re-provision; supervisor replaces sessions per node and tears them
down on node exit/replacement/shutdown.
- The edge pump runs on the engine's blocking pool with sole session
ownership (commands in, state mirror + feed lines out): the connect
handshake blocks its thread and must not run on a Tokio worker or
share a lock with the actor. Connects are bounded (10s) so a dead
node faults its session instead of wedging edge polling.
- iroh-driver: retain_telemetry_connections() opts an application out
of the driver-owned TELEMETRY_ALPN ingress so the node's pull server
can drain those connections itself (the actor-bridge pump would
otherwise claim them).
- Dashboard: edges array in the reconciler snapshot, per-node edge
badges and edge button in Fleet Control, node_edges render mirror.