Merge feat/297-cheaper-ai into feat/299-correlation-simplify

Resolve upload.py (no-scene fallback uses the new _correlate with #298's
non_event_chatter reason) and chatter_classifier docstring (gate built, off by
default). Fold intelligence._llm_bool into incident_correlator.parse_llm_bool (#88).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

drb-c2-core/tests/test_intelligence_llm_bool.py

@@ -0,0 +1,14 @@
+"""server-26#88 — resolved/reassignment are parsed, not bool()-coerced."""
+import pytest
+
+from app.internal.incident_correlator import parse_llm_bool as _llm_bool
+
+
+@pytest.mark.parametrize("value,expected", [
+    (True, True), (False, False),
+    ("true", True), ("TRUE", True), (" Yes ", True), ("yes", True),
+    ("false", False), ("False", False), ("no", False), ("NO", False),
+    ("", False), ("maybe", False), (None, False), (1, False), (0, False), ([], False),
+])
+def test_llm_bool(value, expected):
+    assert _llm_bool(value) is expected