Add JetStream stream/consumer config and data replication across cluster
peers via $JS.INTERNAL.* subjects with BroadcastRoutedMessageAsync (sends
to all peers, bypassing pool routing). Capture routed data messages into
local JetStream stores in DeliverRemoteMessage. Fix leaf node solicited
reconnect by re-launching the retry loop in WatchConnectionAsync after
disconnect.
Unskips 4 of 5 E2E cluster tests (LeaderDies_NewLeaderElected,
R3Stream_NodeDies_PublishContinues, Consumer_NodeDies_PullContinuesOnSurvivor,
Leaf_HubRestart_LeafReconnects). The 5th (LeaderRestart_RejoinsAsFollower)
requires RAFT log catchup which is a separate feature.