fix(tests): set BOARDSMITH_VERBOSE for progress stderr test

The semantic agent only emits progress to stderr when BOARDSMITH_VERBOSE
is set. The test was asserting progress without setting the env var.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: 2 people

tests/agent/test_semantic_agent.py

@@ -311,8 +311,9 @@ def _boom():
         assert result.cap_hit is True
         assert any("tool crashed" in v.get("message", "") for v in result.violations)
 
-    def test_progress_written_to_stderr(self, capsys):
-        """Progress 'Semantic iteration N/max' is written to stderr each iteration."""
+    def test_progress_written_to_stderr(self, capsys, monkeypatch):
+        """Progress 'Semantic iteration N/max' is written to stderr when BOARDSMITH_VERBOSE is set."""
+        monkeypatch.setenv("BOARDSMITH_VERBOSE", "1")
         agent = _make_agent([
             [MISSING_COMP],
             [],  # clean after 1 iteration