feat(narrative): add god_mode.modify_emotion with audit logging

backend/app/services/narrative/god_mode.py

@@ -26,3 +26,36 @@ def inject_event(sim_dir: str, description: str, round_num: Optional[int] = None
         "description": description,
         "round": round_val,
     })
+
+
+def modify_emotion(sim_dir: str, character_id: str, emotions: dict) -> dict:
+    """Overwrite specified emotion values for a character. Clamps to [0, 1].
+
+    Raises ValueError if character_id is not found. Unknown emotion keys are
+    silently ignored (they don't corrupt state; they just don't apply).
+    Logs the intervention to world_state.event_log for auditability.
+    """
+    store = StoryStore(sim_dir)
+    characters = store.load_characters()
+
+    target = next((c for c in characters if str(c.get("id")) == str(character_id)), None)
+    if target is None:
+        raise ValueError(f"character not found: {character_id}")
+
+    current = target["emotional_state"]["current"]
+    changed = {}
+    for emo, val in emotions.items():
+        if emo in current:
+            new_val = max(0.0, min(1.0, float(val)))
+            changed[emo] = {"from": current[emo], "to": new_val}
+            current[emo] = new_val
+
+    store.save_characters(characters)
+
+    WorldStateStore(sim_dir).append_event({
+        "type": "god_mode_emotion_change",
+        "description": f"{target['name']} emotional state modified: {changed}",
+        "round": _current_round(sim_dir),
+    })
+
+    return target

backend/tests/test_god_mode.py

@@ -36,3 +36,49 @@ def test_inject_event_defaults_round_to_beats_plus_one(temp_sim_dir):
 def test_inject_event_defaults_round_to_one_when_no_beats(temp_sim_dir):
     evt = inject_event(temp_sim_dir, description="first event")
     assert evt["round"] == 1
+
+
+# ---- modify_emotion ----
+from app.services.narrative.god_mode import modify_emotion
+
+
+def _seed_character(sim_dir, char_id="1", name="Elena"):
+    store = StoryStore(sim_dir)
+    neutral = {k: 0.0 for k in ["anger", "fear", "joy", "sadness", "surprise"]}
+    store.save_characters([{
+        "id": char_id, "name": name, "status": "alive",
+        "emotional_state": {"current": {**neutral, "trust": 0.5}, "history": []},
+    }])
+    return store
+
+
+def test_modify_emotion_overwrites_specified_emotions(temp_sim_dir):
+    _seed_character(temp_sim_dir)
+    result = modify_emotion(temp_sim_dir, "1", {"anger": 0.8, "joy": 0.2})
+
+    assert result["emotional_state"]["current"]["anger"] == 0.8
+    assert result["emotional_state"]["current"]["joy"] == 0.2
+    assert result["emotional_state"]["current"]["trust"] == 0.5
+
+
+def test_modify_emotion_clamps(temp_sim_dir):
+    _seed_character(temp_sim_dir)
+    result = modify_emotion(temp_sim_dir, "1", {"anger": 1.5, "fear": -0.3})
+    assert result["emotional_state"]["current"]["anger"] == 1.0
+    assert result["emotional_state"]["current"]["fear"] == 0.0
+
+
+def test_modify_emotion_character_not_found_raises(temp_sim_dir):
+    _seed_character(temp_sim_dir)
+    with pytest.raises(ValueError, match="not found"):
+        modify_emotion(temp_sim_dir, "nonexistent", {"anger": 0.5})
+
+
+def test_modify_emotion_audit_logs_to_event_log(temp_sim_dir):
+    _seed_character(temp_sim_dir)
+    modify_emotion(temp_sim_dir, "1", {"anger": 0.8})
+
+    log = WorldStateStore(temp_sim_dir).load()["event_log"]
+    assert len(log) == 1
+    assert log[0]["type"] == "god_mode_emotion_change"
+    assert "Elena" in log[0]["description"]