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/style.css

@@ -618,6 +618,137 @@ code {
 .diff-hub_only td { color: #3b82f6; }
 .diff-controller_only td { color: #fb923c; }
 
+/* Badge styles */
+.badge {
+    display: inline-block;
+    padding: 0.15rem 0.5rem;
+    border-radius: 0.25rem;
+    font-size: 0.8rem;
+    font-weight: 600;
+    font-family: var(--font-mono);
+}
+.badge-error {
+    background: rgba(248, 113, 113, 0.2);
+    color: var(--red);
+}
+.badge-warn {
+    background: rgba(250, 204, 21, 0.2);
+    color: var(--yellow);
+}
+
+/* Summary cards row */
+.summary-cards {
+    display: flex;
+    gap: 1rem;
+    margin-bottom: 1.5rem;
+    flex-wrap: wrap;
+}
+.summary-card {
+    flex: 1;
+    min-width: 160px;
+    background: var(--bg-card);
+    border: 1px solid var(--border);
+    border-radius: 0.5rem;
+    padding: 1rem 1.25rem;
+}
+.summary-card .card-number {
+    font-size: 2rem;
+    font-weight: 700;
+    color: var(--text-primary);
+    font-family: var(--font-mono);
+    line-height: 1.1;
+}
+.summary-card .card-label {
+    font-size: 0.8rem;
+    color: var(--text-muted);
+    margin-top: 0.25rem;
+}
+
+/* Chart container */
+.chart-container {
+    position: relative;
+    width: 100%;
+    height: 280px;
+    margin: 1rem 0;
+}
+
+/* Period selector button group */
+.period-selector {
+    display: flex;
+    gap: 0.25rem;
+    margin-bottom: 1rem;
+}
+.period-btn {
+    padding: 0.3rem 0.75rem;
+    border: 1px solid var(--border);
+    border-radius: 0.25rem;
+    background: var(--bg-secondary);
+    color: var(--text-secondary);
+    font-size: 0.85rem;
+    text-decoration: none;
+    cursor: pointer;
+    transition: background 0.15s, color 0.15s;
+}
+.period-btn:hover, .period-btn.active {
+    background: var(--accent);
+    color: var(--bg-primary);
+    border-color: var(--accent);
+}
+
+/* Accuracy dot */
+.accuracy-dot {
+    display: inline-block;
+    width: 10px;
+    height: 10px;
+    border-radius: 50%;
+    margin-left: 0.25rem;
+}
+.accuracy-ok   { background: var(--green); }
+.accuracy-warn { background: var(--yellow); }
+.accuracy-danger { background: var(--red); }
+
+/* Memory color classes */
+.mem-ok     { color: var(--green); }
+.mem-warn   { color: var(--yellow); }
+.mem-danger { color: var(--red); }
+
+/* Data table (apps page) */
+.data-table {
+    width: 100%;
+    border-collapse: collapse;
+    font-size: 0.9rem;
+}
+.data-table th {
+    text-align: left;
+    padding: 0.6rem 0.75rem;
+    font-weight: 600;
+    color: var(--text-secondary);
+    font-size: 0.8rem;
+    text-transform: uppercase;
+    letter-spacing: 0.04em;
+    border-bottom: 1px solid var(--border);
+    white-space: nowrap;
+}
+.data-table td {
+    padding: 0.6rem 0.75rem;
+    border-bottom: 1px solid rgba(100,116,139,0.15);
+    color: var(--text-primary);
+    font-family: var(--font-mono);
+    font-size: 0.875rem;
+}
+.data-table td a {
+    color: var(--accent);
+    text-decoration: none;
+    font-family: var(--font-sans, sans-serif);
+}
+.data-table td a:hover { text-decoration: underline; }
+.data-table th a {
+    color: var(--text-secondary);
+    text-decoration: none;
+}
+.data-table th a:hover { color: var(--text-primary); }
+.data-table tr:hover td { background: rgba(96,165,250,0.04); }
+
 /* Responsive */
 @media (max-width: 768px) {
     .container { padding: 1rem; }