@app.route('/api/usage', methods=['GET'])
@api_login_required
def get_usage_stats():
    """返回当前用户的模型/搜索调用统计。"""
    username = get_current_username()
    tracker = get_or_create_usage_tracker(username)
    if not tracker:
        return jsonify({"success": False, "error": "未找到用户"}), 404
    return jsonify({
        "success": True,
        "data": tracker.get_stats()
    })