9 tests for generate_response_per_subquestion() and answer format validation covering multi-sub-q, empty, prompt construction, and markdown format. 8 tests for new history XML/JSON formats (sources as list-of-lists, <sub_q> wrappers in XML) and new {context_sections} prompt template.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Woody