fix: silence aiohttp.access log and strip plugin prefix in alerts UI

- main: disable aiohttp.access propagation unless --debug is active
- alerts.html: strip plugin-name prefix from metric_path display
  (nagios_runner.check_disk_root_status_code → check_disk_root_status_code)

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

hbd/server/main.py

@@ -475,7 +475,8 @@ def run(config, config_path=None):
     if config.get("debug", 0) > 0:
         log_level = logging.DEBUG
     logging.basicConfig(level=log_level)
-    logging.getLogger("aiohttp.access").setLevel(logging.DEBUG)
+    if not config.get("debug", 0):
+        logging.getLogger("aiohttp.access").propagate = False
     load_pickled_hosts(config, hbdclass)
 
     notify_mod.initlog(logfile=config.get("logfile", "messages.log"))