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>

plugins/host_agent/templates/widget_history.html

@@ -16,16 +16,14 @@
      toggle that re-requests this widget without entering edit mode. #}
   <div style="flex:0 0 auto;display:flex;align-items:center;gap:0.5rem;flex-wrap:wrap;font-size:0.75rem;color:var(--text-muted);margin-bottom:0.3rem;">
     {% if session.user_id %}
-    <a href="/hosts/{{ host.id }}" style="font-weight:600;">{{ host.name }}</a>
+    <a href="/hosts/{{ host.id }}" style="font-weight:500;">{{ host.name }}</a>
     {% else %}
     <strong style="color:var(--text);">{{ host.name }}</strong>
     {% endif %}
-    <span class="hist-range" style="margin-left:auto;display:inline-flex;border:1px solid var(--border-mid);border-radius:5px;overflow:hidden;">
+    <span class="hist-range" style="margin-left:auto;display:inline-flex;gap:0.25rem;">
       {% for opt in [1, 6, 24] %}
       <button type="button" onclick="histRange({{ wid|int }}, {{ opt|int }})"
-        style="border:0;cursor:pointer;padding:0.1rem 0.45rem;font-size:0.72rem;
-               background:{% if opt == hours %}var(--accent){% else %}transparent{% endif %};
-               color:{% if opt == hours %}#fff{% else %}var(--text-muted){% endif %};">{{ opt }}h</button>
+        class="range-btn{% if opt == hours %} active{% endif %}">{{ opt }}h</button>
       {% endfor %}
     </span>
   </div>
@@ -57,9 +55,9 @@ window.histRange = function (wid, hours) {
     return ("0" + d.getHours()).slice(-2) + ":" + ("0" + d.getMinutes()).slice(-2);
   };
   var ds = [
-    { key: "cpu_pct",      label: "CPU %",    color: "#c8a840" },
-    { key: "mem_used_pct", label: "Mem %",    color: "#4aa86a" },
-    { key: "disk_root",    label: "Disk / %", color: "#c87840" },
+    { key: "cpu_pct",      label: "CPU %",    color: stewardColor("--gold") },
+    { key: "mem_used_pct", label: "Mem %",    color: stewardColor("--green") },
+    { key: "disk_root",    label: "Disk / %", color: stewardColor("--yellow") },
   ];
   new Chart(el.getContext("2d"), {
     type: "line",
@@ -75,14 +73,14 @@ window.histRange = function (wid, hours) {
       interaction: { mode: "index", intersect: false },
       elements: { point: { radius: 0 } },
       scales: {
-        x: { type: "linear", ticks: { callback: function (v) { return fmtTime(v); }, maxTicksLimit: 6, color: "#8a8a92", font: { size: 10 } }, grid: { color: "#30303a" } },
+        x: { type: "linear", ticks: { callback: function (v) { return fmtTime(v); }, maxTicksLimit: 6, font: { size: 10 } } },
         // Fixed 0–{{ y_max }} ceiling (server snaps the data peak up to the next
         // 10% band). Steady across refreshes — auto-scaling made the zoom jump on
         // every poll — while a banded ceiling still keeps the lines filling the panel.
-        y: { min: 0, max: {{ y_max }}, ticks: { color: "#8a8a92", font: { size: 10 } }, grid: { color: "#30303a" } },
+        y: { min: 0, max: {{ y_max }}, ticks: { font: { size: 10 } } },
       },
       plugins: {
-        legend: { labels: { color: "#b8b8b0", boxWidth: 10, font: { size: 11 } } },
+        legend: { labels: { boxWidth: 10, font: { size: 11 } } },
         tooltip: { callbacks: { title: function (items) { return items.length ? fmtTime(items[0].parsed.x) : ""; } } },
       },
     },