feat: add OpenProject 17 docker compose stack and test data seeder

- Configure OpenProject 17 with PostgreSQL 17 and Memcached

- Add scripts/seed-test-data.rb for test project, work packages, and API key generation

- Add scripts/seed.sh to orchestrate container health check and seed execution

- Add scripts/start.sh and scripts/stop.sh stack lifecycle helpers

- Provide .env.example with defaults

scripts/stop.sh

@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+# ==============================================================================
+# OpenProject MCP Companion - Stop Stack
+# ==============================================================================
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+ROOT_DIR="$(cd "${SCRIPT_DIR}/.." && pwd)"
+
+echo "[stop.sh] Stopping OpenProject docker compose stack..."
+docker compose -f "${ROOT_DIR}/docker-compose.yml" down
+echo "[stop.sh] Stack stopped."