Harden max_cache_rows against invalid env override

Catch ValueError when CLAUDE_CODE_CHAT_BROWSER_SUMMARY_CACHE_MAX_ROWS is not an integer and fall back to DEFAULT_MAX_ROWS so put_summary() does not fail on the session-list path.

Author: clean6378-max-it

tests/test_session_summary_cache.py

@@ -43,6 +43,24 @@ def test_rules_fingerprint_empty() -> None:
     assert rules_fingerprint([]) == "none"
 
 
+def test_max_cache_rows_invalid_env_falls_back(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.setenv("CLAUDE_CODE_CHAT_BROWSER_SUMMARY_CACHE_MAX_ROWS", "not-a-number")
+    from utils.session_summary_cache import DEFAULT_MAX_ROWS, max_cache_rows
+
+    assert max_cache_rows() == DEFAULT_MAX_ROWS
+
+
+def test_max_cache_rows_valid_env_enforces_minimum(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    monkeypatch.setenv("CLAUDE_CODE_CHAT_BROWSER_SUMMARY_CACHE_MAX_ROWS", "0")
+    from utils.session_summary_cache import max_cache_rows
+
+    assert max_cache_rows() == 1
+
+
 def test_rules_fingerprint_stable() -> None:
     rules = [[("word", "secret")]]
     assert rules_fingerprint(rules) == rules_fingerprint(rules)

utils/session_summary_cache.py

@@ -22,7 +22,10 @@ def max_cache_rows() -> int:
     raw = os.environ.get("CLAUDE_CODE_CHAT_BROWSER_SUMMARY_CACHE_MAX_ROWS", "").strip()
     if not raw:
         return DEFAULT_MAX_ROWS
-    return max(1, int(raw))
+    try:
+        return max(1, int(raw))
+    except ValueError:
+        return DEFAULT_MAX_ROWS
 
 
 _lock = threading.Lock()