Add worktree sandbox and test env workflow

scripts/worktree-up.sh

@@ -0,0 +1,30 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+REPO_ROOT=$(cd "${SCRIPT_DIR}/.." && pwd)
+DEFAULT_SANDBOX="${REPO_ROOT}/../galaxyforge-sandbox"
+SANDBOX_PATH="${1:-$DEFAULT_SANDBOX}"
+
+if [[ "$SANDBOX_PATH" != /* ]]; then
+  SANDBOX_PATH="${REPO_ROOT}/${SANDBOX_PATH}"
+fi
+
+SANDBOX_PATH=$(realpath -m "$SANDBOX_PATH")
+
+"${SCRIPT_DIR}/worktree-sync.sh" "$SANDBOX_PATH"
+
+if [[ ! -f "$SANDBOX_PATH/docker-compose.yml" ]]; then
+  echo "Fehler: docker-compose.yml fehlt in der Sandbox: $SANDBOX_PATH" >&2
+  exit 1
+fi
+
+(
+  cd "$SANDBOX_PATH"
+  docker compose up -d --build
+)
+
+echo "Sandbox laeuft. URLs:"
+echo "- http://localhost/"
+echo "- http://localhost/m"
+echo "- http://localhost/api/health"