switch-service.sh waits for the service's protected sessions to be idle (two checks a minute apart, up to 12 hours) before stopping it: a Media switch must not cut a recording.

ddiff --git a/roles/data/switch-service.sh b/roles/data/switch-service.sh
iindex 37a9bf3..28567ff 100755
---- a/roles/data/switch-service.sh
++++ b/roles/data/switch-service.sh
@@@ -5,7 +5,8 @@
  #
  # Before: the service's postgres branch is merged to main with green CI, its auto-deploy is frozen
  # (ovhost freeze <svc> --reason …), and add-service.sh <svc> has written its database settings.
--# It clones main as ubuntu into /var/tmp/pg-<svc> and installs it; stops the unit; keeps a read-only
++# It clones main as ubuntu into /var/tmp/pg-<svc> and installs it; waits until the service's protected sessions are
++# idle (two checks a minute apart); stops the unit; keeps a read-only
  # <svc>.pre-postgres-<time>.db backup next to the file; runs that release's scripts/migrate-to-postgres.js
  # (openvibe-sdk runSqliteMigration: migrate, import, verify counts and checksums) with the unit's
  # environment, as ubuntu; on any failure it starts the old release again and stops. Then it unfreezes and
@@@ -20,17 +21,29 @@ WORK=/var/tmp/pg-$SVC; UB=$(id -u ubuntu); GB=$(id -g ubuntu)
  rm -rf "$WORK"; install -d -o ubuntu -g ubuntu "$WORK"
  REMOTE=$(git -C "$DIR" remote get-url origin)
  setpriv --reuid=$UB --regid=$GB --init-groups env HOME=/home/ubuntu bash -c "cd $WORK && git clone -q --depth 1 --branch main '$REMOTE' src && cd src && npm ci --omit=dev --no-audit --no-fund 2>&1 | tail -1 && git log --oneline -1"
++# Protected sessions (the inventory's probe: Media's recordings, Live's streams) would be cut by the stop: wait for two
++# idle checks a minute apart, as a deploy's --wait-idle does, for up to 12 hours. A probe that cannot answer counts as busy.
++quiet=0
++for _ in $(seq 1 720); do
++    n=$(ovhost status "$SVC" --json | node -e 'const r = JSON.parse(require("fs").readFileSync(0, "utf8"))[0] || {}; const p = r.protected; process.stdout.write(!p ? "none" : p.count == null ? "unknown" : String(p.count));')
++    [ "$n" = none ] && break
++    if [ "$n" = 0 ]; then quiet=$((quiet + 1)); [ $quiet -ge 2 ] && break; else quiet=0; echo "[switch] waiting: $n protected session(s)"; fi
++    sleep 60
++done
++[ "$n" = none ] || [ $quiet -ge 2 ] || { echo "[switch] still busy after 12 hours: not switching"; rm -rf "$WORK"; exit 1; }
  echo "[switch] stopping $UNIT"; systemctl stop "$UNIT"
  sqlite3 "$DB" ".backup $WORK/source.db"; chown ubuntu:ubuntu "$WORK/source.db"
  TS=$(date -u +%Y%m%dT%H%M%SZ); cp "$WORK/source.db" "$DATA/$SVC.pre-postgres-$TS.db"; chmod 0400 "$DATA/$SVC.pre-postgres-$TS.db"; echo "[switch] backup $DATA/$SVC.pre-postgres-$TS.db"
  echo "[switch] importing"
--set -a; . /etc/openvibe/$SVC.env; set +a
--ENVS=$(systemctl show "$UNIT" -p Environment --value); [ -n "$ENVS" ] && export $ENVS >/dev/null
--cd "$WORK/src"
--if ! setpriv --reuid=$UB --regid=$GB --init-groups env HOME=/home/ubuntu node scripts/migrate-to-postgres.js --sqlite "$WORK/source.db" 2>&1 | grep -v " 0 rows"; then
++# The unit's own environment, parsed by systemd (EnvironmentFile= and Environment=): sourcing the file with bash would
++# mangle values systemd reads fine (JSON, quotes). As ubuntu, in the release just installed.
++SETENV=(); while IFS= read -r kv; do [ -n "$kv" ] && SETENV+=(-E "$kv"); done < <(systemctl show "$UNIT" -p Environment --value | tr ' ' '\n')
++ENVFILES=(); for f in $(systemctl show "$UNIT" -p EnvironmentFiles --value | grep -o '^[^ ]*\|; [^ ]*' | tr -d '; '); do ENVFILES+=(-p "EnvironmentFile=$f"); done
++[ ${#ENVFILES[@]} -gt 0 ] || ENVFILES=(-p "EnvironmentFile=/etc/openvibe/$SVC.env")
++if ! systemd-run --quiet --wait --pipe --collect --uid="$UB" --gid="$GB" -p WorkingDirectory="$WORK/src" -E HOME=/home/ubuntu "${ENVFILES[@]}" "${SETENV[@]}" \
++        "$(command -v node)" scripts/migrate-to-postgres.js --sqlite "$WORK/source.db" 2>&1 | grep -v " 0 rows"; then
      echo "[switch] IMPORT FAILED: starting the old release again"; systemctl start "$UNIT"; exit 1
  fi
--cd /
  echo "[switch] deploying"
  ovhost unfreeze "$SVC" >/dev/null
  ovhost deploy "$SVC" 2>&1 | tail -3