fix(qa-synthesizer): read the schema router.ai() actually returns

[hdimer]

Summary

• run_qa_synthesizer read result.parsed off the return of router.ai(..., schema=QASynthesisResult). The SDK returns the validated schema instance directly, so that raised AttributeError, the broad except Exception swallowed it, and the function fell through to the tests_passed/review_approved heuristic on every call. The synthesizer's decision was never used. Fixes AgentField router.ai returns a QASynthesisResult directly, while SWE-AF expects an older wrapper with .parsed #113.
• This is the only affected call site. run_qa_synthesizer is the one reasoner in the module that calls router.ai(); the eighteen other LLM-calling agents use router.harness(), whose HarnessResult really does carry .parsed. They are correct and untouched.

I used isinstance(result, QASynthesisResult) rather than a getattr(result, "parsed", result) compatibility shim, because AgentAI.ai(..., schema=X) returns schema(**json_data) in both 0.1.113 (this repo's floor pin) and current 0.1.132, so there is no wrapper to fall back to on any supported version. The type gate also routes the one remaining non-schema return, a ToolCallResponse when the model content is not parseable JSON, to the heuristic fallback deliberately and with its own note, rather than through a swallowed AttributeError. Happy to switch to the shim if you would rather keep the older shape working.

Validation

• make check - 1210 passed, 1 skipped (1208 passed before this change)
• Relevant manual test performed (if needed)

Two tests in tests/test_qa_synthesizer_direct_schema.py, both run against the unpatched file first to confirm they fail for the right reason. The first feeds inputs the heuristic resolves to approve while the synthesizer returns block, so only the real decision can produce block. The second fails if the non-schema path ever stops logging.

Behavior Impact

• No behavior change
• Backward compatible behavior change
• Breaking change (explain below)

Notes

Worth a look before merge, since this un-deadens two paths rather than just silencing an error:

• action is now the synthesizer's judgement instead of the heuristic's. block was previously reachable only when the reviewer set blocking; it can now come from the synthesizer alone, and coding_loop.py:765 turns that into FAILED_UNRECOVERABLE.
• stuck from the synthesizer was always False, so coding_loop.py:687 only ever saw the _detect_stuck_loop backstop at :809. The synthesizer's own stuck signal becomes load-bearing here for the first time.

Both are the behaviour of the code as written, but they are newly live, and by default they are driven by a haiku-class model. If you would prefer to land the fix without switching those on in the same change, say so and I will split it.

Written with AI assistance (Claude). I reviewed, tested, and verified the SDK behaviour myself.

[CLAassistant]

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