feat(hub): app telemetry analytics dashboard (v0.4.0)

- store/telemetry.go: new app_telemetry + app_log_issues tables with
  SaveAppTelemetry, GetFleetAppSummary (with P95), GetAppTelemetryHistory,
  GetAppCustomerBreakdown, GetCustomerAppSummary, GetAppIssues, prune methods
- api/handler.go: parse and save optional app_telemetry from report body,
  backward-compatible with old controllers
- cmd/hub/main.go: prune app_telemetry (90d) and stale issues (30d)
- web/apps.go: handleApps + handleAppDetail + chart data aggregation helpers
- web/server.go: routes for /apps, /apps/{name}, /static/chart.min.js;
  added memoryColor/accuracyClass/gt template functions
- web/embed.go: embed static/chart.min.js
- web/configs.go: add app telemetry section to handleCustomerUnified
- templates/apps.html: fleet-wide app list with summary cards and sortable table
- templates/app_detail.html: per-app page with Chart.js memory trend,
  customer breakdown, and known issues table
- templates/customer_unified.html: new Alkalmazás telemetria card
- templates/style.css: badge, summary-card, chart, period-selector,
  accuracy-dot, mem-color, data-table styles
- All templates: added Alkalmazások nav link

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

hub/internal/web/templates/customer_unified.html

@@ -15,6 +15,7 @@
             <nav class="nav-links" style="margin-bottom: 0.5rem;">
                 <a href="/" class="nav-link">Dashboard</a>
                 <a href="/configs" class="nav-link active">Customers</a>
+                <a href="/apps" class="nav-link">Alkalmazások</a>
             </nav>
             <a href="/configs" class="back-link">&larr; All Customers</a>
             <h1>
@@ -470,6 +471,39 @@
             {{end}}
         </section>
 
+        <!-- Alkalmazás telemetria -->
+        {{if .HasAppTelemetry}}
+        <section class="card">
+            <h2>Alkalmazás telemetria <span class="text-muted" style="font-size: 0.85em; font-weight: normal;">(utolsó 7 nap)</span></h2>
+            <table class="data-table">
+                <thead>
+                    <tr>
+                        <th>Alkalmazás</th>
+                        <th>Memória (jelenlegi)</th>
+                        <th>Memória (átlag 7d)</th>
+                        <th>Memória (csúcs 7d)</th>
+                        <th>Katalógus limit</th>
+                        <th>Hibák</th>
+                        <th>Figyelmeztetések</th>
+                    </tr>
+                </thead>
+                <tbody>
+                    {{range .AppTelemetry}}
+                    <tr>
+                        <td><a href="/apps/{{.AppName}}">{{if .DisplayName}}{{.DisplayName}}{{else}}{{.AppName}}{{end}}</a></td>
+                        <td class="{{memoryColor .MemoryCurrentMB .CatalogLimit}}">{{formatFloat .MemoryCurrentMB}} MB</td>
+                        <td>{{formatFloat .MemoryAvgMB}} MB</td>
+                        <td>{{formatFloat .MemoryPeakMB}} MB</td>
+                        <td>{{if .CatalogLimit}}{{.CatalogLimit}}{{else}}—{{end}}</td>
+                        <td>{{if gt .LogErrors 0}}<span class="badge badge-error">{{.LogErrors}}</span>{{else}}0{{end}}</td>
+                        <td>{{if gt .LogWarnings 0}}<span class="badge badge-warn">{{.LogWarnings}}</span>{{else}}0{{end}}</td>
+                    </tr>
+                    {{end}}
+                </tbody>
+            </table>
+        </section>
+        {{end}}
+
         <!-- Notifications -->
         <section class="card">
             <h2>Notifications</h2>