fix(cli): silence tirith prefetch install warnings at startup (#1452)

tests/tools/test_tirith_security.py

@@ -315,6 +315,23 @@ class TestEnsureInstalled:
             mock_thread.start.assert_called_once()
         _tirith_mod._resolved_path = None
 
+    @patch("tools.tirith_security._load_security_config")
+    def test_startup_prefetch_can_suppress_install_failure_logs(self, mock_cfg):
+        mock_cfg.return_value = {"tirith_enabled": True, "tirith_path": "tirith",
+                                 "tirith_timeout": 5, "tirith_fail_open": True}
+        _tirith_mod._resolved_path = None
+        with patch("tools.tirith_security.shutil.which", return_value=None), \
+             patch("tools.tirith_security._hermes_bin_dir", return_value="/nonexistent"), \
+             patch("tools.tirith_security._is_install_failed_on_disk", return_value=False), \
+             patch("tools.tirith_security.threading.Thread") as MockThread:
+            mock_thread = MagicMock()
+            MockThread.return_value = mock_thread
+            result = ensure_installed(log_failures=False)
+            assert result is None
+            assert MockThread.call_args.kwargs["kwargs"] == {"log_failures": False}
+            mock_thread.start.assert_called_once()
+        _tirith_mod._resolved_path = None
+
 
 # ---------------------------------------------------------------------------
 # Failed download caches the miss (Finding #1)
@@ -516,6 +533,22 @@ class TestCosignVerification:
         assert path is None
         assert reason == "cosign_missing"
 
+    @patch("tools.tirith_security.logger.debug")
+    @patch("tools.tirith_security.logger.warning")
+    @patch("tools.tirith_security.shutil.which", return_value=None)
+    @patch("tools.tirith_security._download_file")
+    @patch("tools.tirith_security._detect_target", return_value="aarch64-apple-darwin")
+    def test_install_quiet_mode_downgrades_cosign_missing_log(self, mock_target, mock_dl,
+                                                              mock_which, mock_warning,
+                                                              mock_debug):
+        """Startup prefetch should not surface cosign-missing as a warning."""
+        from tools.tirith_security import _install_tirith
+        path, reason = _install_tirith(log_failures=False)
+        assert path is None
+        assert reason == "cosign_missing"
+        mock_warning.assert_not_called()
+        mock_debug.assert_called()
+
     @patch("tools.tirith_security._verify_cosign", return_value=None)
     @patch("tools.tirith_security.shutil.which", return_value="/usr/local/bin/cosign")
     @patch("tools.tirith_security._download_file")