eventlog: store structured dicts; filter by user; clock: fix minute hand step

- eventlog() now stores {ts, host, level, service, message} dicts instead of strings
- WebSocket sends/broadcasts filter event log messages by the user's managed hosts
- live.html renders structured log entries with level-coloured spans
- Swiss railway clock minute hand now holds until second hand reaches 12, then steps

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

hbd/server/notify.py

@@ -106,11 +106,18 @@ def closelog():
 
 def eventlog(host, lvl, m, service=None):
     ts = time.time()
+    msg = {
+        "ts": ts,
+        "host": host or None,
+        "level": lvl,
+        "service": service,
+        "message": m,
+    }
+    data.msgs.append(msg)
     s = f"{time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(ts))} {lvl} "
     if host:
         s += f"{host} "
     s += m
-    data.msgs.append(s)
     logger.info(s)
     if logf:
         try:
@@ -118,7 +125,7 @@ def eventlog(host, lvl, m, service=None):
             logf.flush()
         except Exception as e:
             logger.warning("failed to write to logfile: %s", e)
-    msg_to_websockets("message", s)
+    msg_to_websockets("message", msg)
 
 
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