fix(ci): free stale vite preview port before mock e2e.

Act hostexecutor leaves zombie preview (cwd deleted) on :4173 returning 404; Playwright waits for 2xx and times out. Refs EventHub/EventHubFrontAdmin#40

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/free-e2e-port.sh

@@ -0,0 +1,38 @@
+#!/usr/bin/env bash
+# Act hostexecutor делит сеть с хостом: после cancel/fail остаётся vite preview
+# с cwd (deleted), порт занят, HTTP 404 → Playwright webServer ждёт 2xx до таймаута.
+set -euo pipefail
+
+PORT="${E2E_PORT:-4173}"
+
+free_port() {
+  local pids=""
+  if command -v fuser >/dev/null 2>&1; then
+    fuser -k "${PORT}/tcp" >/dev/null 2>&1 || true
+    return 0
+  fi
+  if command -v lsof >/dev/null 2>&1; then
+    pids="$(lsof -t -iTCP:"${PORT}" -sTCP:LISTEN 2>/dev/null || true)"
+  elif command -v ss >/dev/null 2>&1; then
+    pids="$(ss -ltnp "sport = :${PORT}" 2>/dev/null | sed -n 's/.*pid=\([0-9]\+\).*/\1/p' | sort -u || true)"
+  fi
+  if [[ -n "${pids}" ]]; then
+    echo "free-e2e-port: killing PIDs on :${PORT}: ${pids}"
+    # shellcheck disable=SC2086
+    kill ${pids} 2>/dev/null || true
+    sleep 1
+    # shellcheck disable=SC2086
+    kill -9 ${pids} 2>/dev/null || true
+  fi
+}
+
+echo "free-e2e-port: ensuring :${PORT} is free"
+free_port
+if command -v ss >/dev/null 2>&1; then
+  if ss -ltn | grep -qE ":${PORT}\\s"; then
+    echo "WARN: :${PORT} still in use after free attempt" >&2
+    ss -ltnp | grep ":${PORT}" || true
+  else
+    echo "free-e2e-port: :${PORT} is free"
+  fi
+fi