test(team-delete): verify DELETE /api/teams/{idx} tears a team down completely

Created a scratch team 5, booted all 16 of its containers, snapshotted its
footprint, deleted it via the API, and re-snapshotted:

  before: 16 containers, 1 sidecar, team5_default network, teams/team5 dir
  after : 0 containers, 0 sidecars, network gone, dir GONE, 34 UFW ports
          closed, Traefik domain removed, 0 score rows
  took 102s; the other 4 teams (64 containers, receivers active) were
  untouched and still at 64/64 SLA.

Adds panel/team_footprint.sh (before/after proof of a delete),
team_health.sh, watch_load.sh.

panel/team_health.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+# Health of every real team: container count, receiver unit, disk.
+set -uo pipefail
+cd /opt/gemastik18-final
+for i in 1 2 3 4; do
+  printf "team%s: %2s containers | receiver=%s | team dir=%s\n" "$i" \
+    "$(docker ps --format '{{.Names}}' | grep -c "_container_team${i}\$")" \
+    "$(systemctl is-active "gemastik-receiver-team${i}.service")" \
+    "$([ -d "teams/team${i}" ] && echo ok || echo MISSING)"
+done
+echo "panel: $(systemctl is-active gemastik-panel)"
+df -h / | tail -1