fix(eval): ignore non-positive recorded attempt numbers

A corrupt-but-valid-JSON cell.json marker (attempt -1 or 0) would lower
the high-water mark and produce attempt-000, violating the 1-based
numbering contract. Only positive integers count.

Author: solomonneas

src/brigade/model_trials.py

@@ -342,7 +342,7 @@ def _attempt_number(cell_dir: Path) -> int:
     )
     recorded = _load_json(cell_dir / "cell.json") or {}
     prior = recorded.get("attempt")
-    if isinstance(prior, int) and not isinstance(prior, bool):
+    if isinstance(prior, int) and not isinstance(prior, bool) and prior > 0:
         numbers.append(prior)
     return max(numbers, default=0) + 1
 

tests/test_model_trials.py

@@ -97,6 +97,14 @@ def test_attempt_number_counts_running_marker_without_attempt_dir(tmp_path):
     assert model_trials._attempt_number(tmp_path) == 2
 
 
+def test_attempt_number_ignores_nonpositive_recorded_attempt(tmp_path):
+    # Corrupt-but-valid-JSON markers must not produce attempt-000.
+    (tmp_path / "cell.json").write_text(json.dumps({"state": "running", "attempt": -1}))
+    assert model_trials._attempt_number(tmp_path) == 1
+    (tmp_path / "cell.json").write_text(json.dumps({"state": "running", "attempt": 0}))
+    assert model_trials._attempt_number(tmp_path) == 1
+
+
 def test_expand_cells_is_stable_and_conditions_change_identity():
     first = model_trials.expand_cells(_manifest(), _roster())
     second = model_trials.expand_cells(_manifest(), _roster())