qa(inspect): metaphor-deflection sidecar (METAPHORICAL_DEFLECTION smell)

Empirically motivated by the 2026-05-02 emergent log:

  Q: 'How can a swallowtail butterfly, gracefully fluttering amidst
      the rockiest terrain, remain undeterred by the upbraiding
      winds...'
  A: 'The Macleay's Swallowtail butterfly is found in Eastern
      Australia including the ACT, New South Wales, Queensland...'

The model traded the metaphor for literal Macleay's-Swallowtail
taxonomic facts. Warrant passed (the literal anchor IS in cited
spans), DEFLECTION_DETECTED didn't fire (the last content token
'flight' did echo somewhere), the bench landed HYBRID 3/3 — but
the user's metaphorical question was never engaged.

Honest gap: catching this structurally requires NLI-grade
semantics, which is the verifier-semantic-gap design proposal.
Until that lands, ship a SMELL SIDECAR — purely lexical, sidecar
only, never enters the binary verifier output.

Detection rule:
  1. Extract metaphor cues from the question:
     - -ly adverbs (gracefully, defiantly), excluding common
       -ly nouns (butterfly, italy, july) via blocklist
     - -ing present participles >=6 chars (upbraiding,
       fluttering, brooding), excluding common verb -ing forms
     - -est superlatives >=6 chars (rockiest, harshest)
     - prepositional cues (amidst, despite, against, beneath)
  2. Count overlap with answer's content tokens.
  3. Fire metaphor_deflection when:
       cue_count >= 3  AND  answer_overlap_count == 0
     The threshold is conservative; the smell only triggers on
     STRONGLY poetic questions with PURELY literal answers.

Wire-up:
  - aborist/qa/inspect.py:diagnose_metaphor_deflection
  - bench/qa_sweep.py: rows gain metaphor_deflection_kind +
    metaphor_cue_count + metaphor_overlap_count
  - scripts/bench_emergent.py: same fields on emergent log rows

5 new tests in tests/test_inspect.py:
  - swallowtail canary case fires metaphor_deflection
  - literal questions (mona lisa) return no_signal
  - questions whose answer engages cues return no_signal
  - common -ly nouns (butterfly, italy, july, family) filtered
  - sub-threshold cue counts return no_signal

756/34 tests pass (5 new + 751 prior).

tests/test_inspect.py

@@ -22,6 +22,7 @@ from aborist.qa.inspect import (
     _classify_span,
     _normalize,
     diagnose_deflection,
+    diagnose_metaphor_deflection,
     diagnose_title_relevance,
     inspect_cache_key,
 )
@@ -604,3 +605,82 @@ def test_title_mismatch_no_claim_tokens():
     """Defensive: empty/stopword-only claim returns no_claim_tokens."""
     d = diagnose_title_relevance("the a an", ["Anything"])
     assert d["kind"] == "no_claim_tokens"
+
+
+# ─────────────────────────────────────────────────────────────────────
+# Metaphor-deflection sidecar
+# ─────────────────────────────────────────────────────────────────────
+
+
+def test_metaphor_deflection_swallowtail_canary():
+    """The original 2026-05-02 emergent log case: swallowtail butterfly
+    question framed metaphorically (gracefully fluttering amidst the
+    rockiest terrain undeterred by upbraiding winds), answer was
+    purely literal taxonomic (Macleay's Swallowtail found in Eastern
+    Australia ...). Sidecar should fire."""
+    q = (
+        "How can a swallowtail butterfly, gracefully fluttering amidst "
+        "the rockiest terrain, remain undeterred by the upbraiding "
+        "winds that seem to challenge its delicate flight?"
+    )
+    a = (
+        "The Macleay's Swallowtail butterfly is found in Eastern "
+        "Australia including the ACT, New South Wales, Queensland, "
+        "Victoria and Tasmania."
+    )
+    d = diagnose_metaphor_deflection(q, a)
+    assert d["kind"] == "metaphor_deflection"
+    # cue_count should pick up at least: amidst, fluttering, gracefully,
+    # rockiest, upbraiding (≥5 real cues; butterfly filtered).
+    assert d["cue_count"] >= 4
+    assert "amidst" in d["cue_tokens"]
+    assert "rockiest" in d["cue_tokens"]
+    assert "upbraiding" in d["cue_tokens"]
+    assert "gracefully" in d["cue_tokens"]
+    assert "butterfly" not in d["cue_tokens"]  # filtered noun
+    assert d["answer_overlap_count"] == 0
+
+
+def test_metaphor_deflection_no_signal_on_literal_question():
+    """Plain factual questions don't have metaphor cues; sidecar
+    returns no_signal."""
+    d = diagnose_metaphor_deflection(
+        "who painted the mona lisa?",
+        "Leonardo da Vinci painted the Mona Lisa around 1503.",
+    )
+    assert d["kind"] == "no_signal"
+    assert d["cue_count"] == 0
+
+
+def test_metaphor_deflection_no_signal_when_answer_engages_cues():
+    """If the answer echoes any of the question's metaphor cues, the
+    sidecar does NOT fire — the model engaged with the framing."""
+    q = "gracefully amidst rockiest terrain undeterred by upbraiding winds"
+    a = "The bird flies gracefully amidst the rockiest terrain undeterred."
+    d = diagnose_metaphor_deflection(q, a)
+    assert d["kind"] == "no_signal"
+    assert d["answer_overlap_count"] >= 1
+
+
+def test_metaphor_deflection_filters_common_ly_nouns():
+    """Naive .endswith('ly') would pick up 'butterfly', 'family',
+    'italy', 'july' etc. as adverbs. The block-list filters them so
+    they don't inflate cue count."""
+    from aborist.qa.inspect import _extract_metaphor_cues
+    cues = _extract_metaphor_cues(
+        "the butterfly flew over italy in july with the family"
+    )
+    # None of the -ly-suffix nouns should appear as cues.
+    for noun in ("butterfly", "italy", "july", "family"):
+        assert noun not in cues, f"{noun} leaked through as a cue"
+
+
+def test_metaphor_deflection_under_threshold_returns_no_signal():
+    """Sidecar requires >=3 cue tokens to fire — a single -ly word
+    isn't enough signal to flag metaphor framing."""
+    d = diagnose_metaphor_deflection(
+        "What gracefully describes a circle?",
+        "A circle is the set of points equidistant from a center.",
+    )
+    assert d["kind"] == "no_signal"
+    assert d["cue_count"] < 3