Flatten nested AutoResearch strategy fields

[FluffyAIcode]

Summary

• flatten nested hypothesis statements and target obligations into validated candidate strings
• incorporate structured plan steps into generated Generator directives
• reject non-string candidate text before hashing or writing candidate.py

Test plan

• python3 -m pytest -q tests/inference_engine/bench/test_autoresearch_supervisor.py tests/inference_engine/bridge/test_agent_gan_repl.py
• python3 -m py_compile autoresearch/prefill/supervisor.py
• reproduced the observed nested hypothesis/plan payload

The uncommitted candidate.py file is runtime state and is excluded.

Made with Cursor

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