feat(plugins): Traefik problems first, UniFi/SNMP/fleet on shared shapes, audit names its entities, templates on tokens (#5126)

Traefik: routers are graded from their latest scrape (router_state: crit on
any real 5xx share, warn on p95 past the latency critical cutoff or a high
4xx share). Failing and slow routers lead as cards that say why; healthy
ones fold into one table that stays open or shut across polls. Proxy
counts are stat tiles; certificates are graded by Settings -> Thresholds
(tls_days).

UniFi: WAN health is a stat strip (latency graded by the thresholds),
devices carry status dots, event categories and firewall actions are
badges, the alarm count reuses .count-badge (renamed from .nav-count).
SNMP: each device wears a status badge and its readings are stat tiles.

Agent fleet: the table comes first, with a Status column (Reporting /
Silent / Never reported, by the host page's stale_after_seconds), silent
agents first, hosts linked, last seen as |ago.

Audit: entries name their entity (one query per type, steward/audit/
service.py) and link it; something deleted since keeps the name its entry
recorded and says "(deleted)".

Tokens: charts read colours through chart-colors.js (stewardColor resolves
a token to the rgb the browser computed; Chart.js defaults take the page's
text and border colours), so host, history, Traefik and SNMP charts drop
their hex. Template hex colours reach 0 (HEX_CEILING = 0), the last rgba
pills go, and heavy weights (600/700/bold, 60 of them) become 500, the
house pair being 400/500; a guard keeps templates there.

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

steward/templates/hosts/list.html

@@ -33,7 +33,7 @@
             {% set hs = host_status.get(host.id) %}
             {% set ut = uptime.get(host.id, {}) %}
             <tr>
-                <td><a href="/hosts/{{ host.id }}" style="font-weight:600;">{{ host.name }}</a></td>
+                <td><a href="/hosts/{{ host.id }}" style="font-weight:500;">{{ host.name }}</a></td>
                 <td style="color:var(--text-muted);">{{ host.address }}</td>
                 <td style="text-align:center;">
                     {% if not hs %}

steward/templates/hosts/overview_widget.html

@@ -16,9 +16,9 @@
             style="flex-shrink:0;"
             title="{% if not hs %}no monitors{% else %}{{ hs.state }}{% endif %}"></span>
       {% if session.user_id %}
-      <a href="/hosts/{{ host.id }}" style="font-weight:600;font-size:0.85rem;overflow-wrap:anywhere;">{{ host.name }}</a>
+      <a href="/hosts/{{ host.id }}" style="font-weight:500;font-size:0.85rem;overflow-wrap:anywhere;">{{ host.name }}</a>
       {% else %}
-      <span style="font-weight:600;font-size:0.85rem;overflow-wrap:anywhere;">{{ host.name }}</span>
+      <span style="font-weight:500;font-size:0.85rem;overflow-wrap:anywhere;">{{ host.name }}</span>
       {% endif %}
     </div>
     {# Line 2 — monitors + agent metrics; wraps instead of truncating #}