feat(gateway): add dashboard session analytics panel

docs/plans/state.json

@@ -50,6 +50,17 @@
       ],
       "test_status": "pnpm test:run src/automation/presets.test.ts src/automation/cron.test.ts src/automation/heartbeat.test.ts src/backup/scheduler.test.ts src/backup/status.test.ts src/tools/builtin/minio-share.test.ts src/tools/policy.test.ts src/config/schema.test.ts src/daemon/channels.test.ts src/gateway/handlers/services.test.ts src/session/store.test.ts src/tools/executor.test.ts src/gateway/handlers/handlers.test.ts + pnpm typecheck passing"
     },
+    "dashboard-session-analytics-panel": {
+      "status": "completed",
+      "date": "2026-02-16",
+      "updated": "2026-02-16",
+      "summary": "Extended the web UI dashboard with a Session Analytics panel backed by `system.sessionAnalytics`, including window summary cards, top tools/topics, top sessions, and daily trend tables refreshed alongside health/services.",
+      "files_modified": [
+        "src/gateway/ui/pages/dashboard.js",
+        "docs/plans/state.json"
+      ],
+      "test_status": "pnpm eslint src/gateway/ui/pages/dashboard.js + pnpm typecheck passing; full pnpm lint currently fails due pre-existing unrelated repo lint errors"
+    },
     "backup-session-summary-audit-trail": {
       "status": "completed",
       "date": "2026-02-16",

src/gateway/ui/pages/dashboard.js

@@ -33,6 +33,21 @@ function formatTime(timestamp) {
   return d.toLocaleTimeString('en-GB', { hour12: false });
 }
 
+function formatDay(day) {
+  const parsed = new Date(`${day}T00:00:00`);
+  if (Number.isNaN(parsed.getTime())) {return day;}
+  return parsed.toLocaleDateString('en-GB', { day: '2-digit', month: 'short' });
+}
+
+function formatNumber(value) {
+  return (value ?? 0).toLocaleString();
+}
+
+function formatSessionDurationFromMessages(avgMessagesPerSession) {
+  if (!avgMessagesPerSession || avgMessagesPerSession <= 0) {return '—';}
+  return `${avgMessagesPerSession.toFixed(1)} msgs/session`;
+}
+
 function escapeHtml(str) {
   const div = document.createElement('div');
   div.textContent = str;
@@ -55,6 +70,11 @@ function renderSkeleton(el) {
       <div class="text-muted text-sm">Loading...</div>
     </div>
 
+    <h2 class="section-title">Session Analytics</h2>
+    <div id="ops-session-analytics">
+      <div class="text-muted text-sm">Loading...</div>
+    </div>
+
     <h2 class="section-title">Event Stream</h2>
     <div class="event-stream" id="ops-events">
       <div class="event-row event-level-info">Loading events...</div>
@@ -217,6 +237,115 @@ function updateActiveRequests(requestsData) {
   `;
 }
 
+function updateSessionAnalytics(analyticsData) {
+  const el = document.getElementById('ops-session-analytics');
+  if (!el) {return;}
+
+  const daily = analyticsData?.daily ?? [];
+  const topSessions = analyticsData?.topSessions ?? [];
+  const topTools = analyticsData?.topTools ?? [];
+  const topTopics = analyticsData?.topTopics ?? [];
+
+  const totalSessions = analyticsData?.totalSessions ?? 0;
+  const totalMessages = analyticsData?.totalMessages ?? 0;
+  const avgMessagesPerSession = analyticsData?.averageMessagesPerSession ?? 0;
+
+  const summaryHtml = `
+    <div class="stats-grid">
+      <div class="stat-card">
+        <div class="stat-label">Sessions (Window)</div>
+        <div class="stat-value">${formatNumber(totalSessions)}</div>
+      </div>
+      <div class="stat-card">
+        <div class="stat-label">Messages (Window)</div>
+        <div class="stat-value">${formatNumber(totalMessages)}</div>
+      </div>
+      <div class="stat-card">
+        <div class="stat-label">Avg Session</div>
+        <div class="stat-value">${formatSessionDurationFromMessages(avgMessagesPerSession)}</div>
+      </div>
+    </div>
+  `;
+
+  const topToolsHtml = topTools.length > 0
+    ? `<ul class="tool-list">${topTools.map((tool) =>
+      `<li><span class="text-accent">${escapeHtml(tool.toolName)}</span> <span class="text-muted">(${formatNumber(tool.executions)})</span></li>`,
+    ).join('')}</ul>`
+    : '<div class="text-muted text-sm">No tool usage captured in this window</div>';
+
+  const topTopicsHtml = topTopics.length > 0
+    ? `<ul class="tool-list">${topTopics.map((topic) =>
+      `<li><span class="text-accent">${escapeHtml(topic.topic)}</span> <span class="text-muted">(${formatNumber(topic.occurrences)})</span></li>`,
+    ).join('')}</ul>`
+    : '<div class="text-muted text-sm">No indexed topics captured in this window</div>';
+
+  const topSessionsHtml = topSessions.length > 0
+    ? `<table>
+      <thead>
+        <tr>
+          <th>Session</th>
+          <th>Messages</th>
+          <th>Last Active</th>
+        </tr>
+      </thead>
+      <tbody>
+        ${topSessions.map((session) => `
+          <tr>
+            <td>${escapeHtml(session.sessionId)}</td>
+            <td>${formatNumber(session.messages)}</td>
+            <td>${timeAgo(session.lastActivity * 1000)}</td>
+          </tr>
+        `).join('')}
+      </tbody>
+    </table>`
+    : '<div class="text-muted text-sm">No session activity in this window</div>';
+
+  const dailyHtml = daily.length > 0
+    ? `<table>
+      <thead>
+        <tr>
+          <th>Day</th>
+          <th>Sessions</th>
+          <th>Messages</th>
+        </tr>
+      </thead>
+      <tbody>
+        ${daily.slice(0, 7).map((row) => `
+          <tr>
+            <td>${formatDay(row.day)}</td>
+            <td>${formatNumber(row.sessions)}</td>
+            <td>${formatNumber(row.messages)}</td>
+          </tr>
+        `).join('')}
+      </tbody>
+    </table>`
+    : '<div class="text-muted text-sm">No daily activity in this window</div>';
+
+  el.innerHTML = `
+    ${summaryHtml}
+    <div class="services-grid">
+      <div class="service-card">
+        <span class="service-name">Top Tools</span>
+        ${topToolsHtml}
+      </div>
+      <div class="service-card">
+        <span class="service-name">Top Topics</span>
+        ${topTopicsHtml}
+      </div>
+    </div>
+    <div class="services-grid">
+      <div class="service-card">
+        <span class="service-name">Top Sessions</span>
+        ${topSessionsHtml}
+      </div>
+      <div class="service-card">
+        <span class="service-name">Daily Trend (Last 7 Rows)</span>
+        ${dailyHtml}
+      </div>
+    </div>
+  `;
+}
+
 function _updateChannels(channelsData) {
   const el = document.getElementById('ops-channels');
   if (!el) {return;}
@@ -285,11 +414,12 @@ async function fetchFast(client) {
 
 async function fetchSlow(client) {
   try {
-    const [health, services] = await Promise.all([
+    const [health, services, sessionAnalytics] = await Promise.all([
       client.call('system.health'),
       client.call('system.services'),
+      client.call('system.sessionAnalytics', { days: 14, topLimit: 5 }),
     ]);
-    return { health, services };
+    return { health, services, sessionAnalytics };
   } catch {
     return null;
   }
@@ -320,6 +450,7 @@ async function loadDashboard(el, client) {
   }
   if (slow) {
     updateServices(slow.services);
+    updateSessionAnalytics(slow.sessionAnalytics);
   }
 
   // Fast refresh: 3 seconds for metrics, events, requests
@@ -341,6 +472,7 @@ async function loadDashboard(el, client) {
       _lastHealth = data.health;
       updateCounters(_lastMetrics, data.health);
       updateServices(data.services);
+      updateSessionAnalytics(data.sessionAnalytics);
     }
   }, 10000);
 }