deploy/hyperborea: production config, user unit, install script, README (wake block pending titan's MAC)

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

deploy/hyperborea/install.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+# Build crossbar for hyperborea (arm64, static) on this machine and install it there as a
+# systemd --user unit. Run from anywhere inside the repo. Idempotent: re-running upgrades in place.
+set -eu
+HOST=${HOST:-hyperborea}
+DIR=/srv/crossbar
+cd "$(git rev-parse --show-toplevel)"
+out=$(mktemp -t crossbar-arm64.XXXXXX)
+trap 'rm -f "$out"' EXIT
+CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -trimpath -ldflags="-s -w" -o "$out" ./cmd/crossbar
+ssh "$HOST" "mkdir -p $DIR ~/.config/systemd/user"
+scp -q "$out" "$HOST:$DIR/crossbar.new"
+scp -q deploy/hyperborea/crossbar.toml "$HOST:$DIR/crossbar.toml"
+scp -q deploy/hyperborea/crossbar.service "$HOST:.config/systemd/user/crossbar.service"
+ssh "$HOST" "chmod 755 $DIR/crossbar.new && mv $DIR/crossbar.new $DIR/crossbar \
+  && systemctl --user daemon-reload && systemctl --user enable crossbar.service >/dev/null 2>&1 \
+  && systemctl --user restart crossbar.service && sleep 2 && systemctl --user is-active crossbar.service"
+echo "installed; hosts view:"
+curl -fsS "http://$HOST.scylla-hammerhead.ts.net:7777/_crossbar/hosts"
+echo