Add guest tally (on air / off air) and host connection warning

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/static/style.css

@@ -38,3 +38,9 @@ button.small{padding:3px 10px;font-size:13px}
 .diag{margin-top:14px;font-size:14px}.diag summary{cursor:pointer}
 .diaglog{max-height:240px;overflow:auto;background:var(--bg);border:1px solid var(--line);border-radius:7px;padding:8px;font-size:12px;white-space:pre-wrap;overflow-wrap:anywhere;margin:0}
 button.on{border-color:var(--ok);color:var(--ok)}
+.tallybar{margin:16px 16px 0;padding:10px 16px;border-radius:8px;text-align:center;font-weight:700;letter-spacing:.06em;border:1px solid var(--line);color:var(--muted);background:var(--card)}
+.tallybar.on,button.tally.on{background:#d11a1a;border-color:#d11a1a;color:#fff}
+.tallybar.on{font-size:20px;letter-spacing:.12em}
+button.tally{font-weight:700;min-width:120px}
+.warnbox{margin:8px 0;padding:8px 12px;border-radius:7px;border:1px solid var(--warn);background:var(--sys);font-size:14px}
+.warnbox.bad{border-color:var(--danger);color:var(--danger);font-weight:600}