feat(F1): configure syslog audit logging for vigilar.alerts

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

tests/unit/test_syslog_config.py

@@ -0,0 +1,7 @@
+"""Test syslog handler configuration for alerts logger."""
+
+
+def test_alerts_logger_name():
+    from vigilar.alerts.sender import log as alerts_log
+
+    assert alerts_log.name == "vigilar.alerts"

vigilar/main.py

@@ -147,6 +147,18 @@ def run_supervisor(cfg: VigilarConfig) -> None:
 
     # Start all subsystems
     log.info("Starting %d subsystems", len(subsystems))
+
+    # Configure syslog handler for alerts audit trail
+    import logging.handlers
+    alerts_logger = logging.getLogger("vigilar.alerts")
+    try:
+        syslog_handler = logging.handlers.SysLogHandler(address="/dev/log")
+        syslog_handler.setFormatter(logging.Formatter("vigilar-alerts: %(message)s"))
+        alerts_logger.addHandler(syslog_handler)
+        log.info("Syslog handler configured for vigilar.alerts")
+    except (OSError, FileNotFoundError):
+        log.warning("Syslog socket not available — alerts will only log to stdout")
+
     for sub in subsystems:
         sub.start()