async indexDocuments(force = false) {
    try {
      const response = await axios.post(`${this.baseUrl}/indexing/start`, { 
        force, 
        background: true 
      });
      return response.data;
    } catch (error) {
      console.error('Error indexing documents:', error);
      throw error;
    }
  }
Start indexing documents in the RAG service
@param {boolean} force - Whether to force refresh from source
@returns {Promise<Object>} - Indexing status