feat(profiler/behave_shell): G.7 emotional_valence.stress_response

Compare median post-error intra-command IATs against baseline
(commands not immediately following an errored command):

* ratio ≥ STRESS_EUSTRESS_RATIO_MIN (1.20) → eustress_positive
* ratio ≤ 1/STRESS_DISTRESS_RATIO_MIN     → distress_negative
* otherwise                                → none

Confidence hard-capped at 0.5; 0.30 below
STRESS_MIN_ERRORED_WITH_IATS (2).

tests/profiler/behave_shell/test_emotional_valence_stress_response.py

@@ -0,0 +1,89 @@
+"""Step G.7: ``emotional_valence.stress_response`` ∈ {none,
+eustress_positive, distress_negative}.
+
+Hard 0.5 confidence cap.
+"""
+from __future__ import annotations
+
+from decnet.profiler.behave_shell import extract_session
+from decnet.profiler.behave_shell._parse import AsciinemaEvent
+
+
+PRIMITIVE = "emotional_valence.stress_response"
+
+
+def _of(observations: list, primitive: str):
+    obs = [o for o in observations if o.primitive == primitive]
+    assert len(obs) == 1, f"expected exactly one {primitive}, got {len(obs)}"
+    return obs[0]
+
+
+def _typed(text: str, t0: float, dt: float = 0.05) -> list[AsciinemaEvent]:
+    return [(t0 + i * dt, "i", c) for i, c in enumerate(text)]
+
+
+def _cmd_with_error(token: str, t0: float, dt: float = 0.05) -> list[AsciinemaEvent]:
+    """Emit one command followed by an error-fingerprint output line."""
+    events = _typed(f"{token}\r", t0=t0, dt=dt)
+    cmd_end = t0 + len(token) * dt
+    events.append((cmd_end + 0.10, "o", "bash: command not found\nanti@host:~$ "))
+    return events
+
+
+def _cmd_ok(token: str, t0: float, dt: float = 0.05) -> list[AsciinemaEvent]:
+    events = _typed(f"{token}\r", t0=t0, dt=dt)
+    cmd_end = t0 + len(token) * dt
+    events.append((cmd_end + 0.10, "o", "out\nanti@host:~$ "))
+    return events
+
+
+def test_no_commands_no_emission() -> None:
+    out = list(extract_session([(0.0, "i", "x")], sid="g7-empty"))
+    assert [o for o in out if o.primitive == PRIMITIVE] == []
+
+
+def test_no_errors_emits_none() -> None:
+    events = _cmd_ok("hostname", t0=0.0) + _cmd_ok("date", t0=2.0)
+    obs = _of(list(extract_session(events, sid="g7-noerr")), PRIMITIVE)
+    assert obs.value == "none"
+
+
+def test_distress_post_error_speed_up() -> None:
+    """After an error, the operator types the next command faster."""
+    events = (
+        _cmd_ok("hostname", t0=0.0, dt=0.20)
+        + _cmd_ok("date", t0=2.0, dt=0.20)
+        + _cmd_with_error("foobar", t0=4.0, dt=0.20)
+        + _cmd_ok("hostname", t0=6.0, dt=0.04)        # post-error: fast
+        + _cmd_with_error("baz", t0=8.0, dt=0.20)
+        + _cmd_ok("date", t0=10.0, dt=0.04)           # post-error: fast
+        + _cmd_ok("hostname", t0=12.0, dt=0.20)
+    )
+    obs = _of(list(extract_session(events, sid="g7-dist")), PRIMITIVE)
+    assert obs.value == "distress_negative"
+
+
+def test_eustress_post_error_slow_down() -> None:
+    """After an error, the operator slows down — deliberate recovery."""
+    events = (
+        _cmd_ok("hostname", t0=0.0, dt=0.04)
+        + _cmd_ok("date", t0=2.0, dt=0.04)
+        + _cmd_with_error("foobar", t0=4.0, dt=0.04)
+        + _cmd_ok("hostname", t0=6.0, dt=0.20)        # post-error: slow
+        + _cmd_with_error("baz", t0=8.0, dt=0.04)
+        + _cmd_ok("date", t0=10.0, dt=0.20)           # post-error: slow
+        + _cmd_ok("hostname", t0=12.0, dt=0.04)
+    )
+    obs = _of(list(extract_session(events, sid="g7-eu")), PRIMITIVE)
+    assert obs.value == "eustress_positive"
+
+
+def test_confidence_capped_at_05() -> None:
+    events = (
+        _cmd_with_error("foobar", t0=0.0, dt=0.05)
+        + _cmd_ok("hostname", t0=2.0, dt=0.20)
+        + _cmd_with_error("baz", t0=4.0, dt=0.05)
+        + _cmd_ok("date", t0=6.0, dt=0.20)
+    )
+    obs = _of(list(extract_session(events, sid="g7-cap")), PRIMITIVE)
+    assert obs.confidence <= 0.50