Align UI with web_template TDS v1.2 standards

- Replace lt-chip priority badges with lt-badge lt-badge-p[1-4] across
  DashboardView, TemplatesView (matches web_template sticky table pattern)
- Add lt-theme-btn theme toggle to header-right; wire lt.theme.toggle()
- Replace ASCII art empty state with lt-empty-state component in dashboard
- Standardize tab wrapper lt-tabs → lt-tab-bar in Dashboard and TicketView
- Add missing lt-keys-help modal to layout_footer (fixes ? key doing nothing)
- Add lt-cmd-overlay command palette container + lt.cmdPalette.init() nav
- Add .lt-timeline-action CSS rule (used in TicketView, was undefined)

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

views/admin/TemplatesView.php

@@ -45,8 +45,8 @@ include __DIR__ . '/../../views/layout_header.php';
               <td data-label="Name"><strong><?= htmlspecialchars($tpl['template_name']) ?></strong></td>
               <td data-label="Category" class="lt-text-xs"><?= htmlspecialchars($tpl['category'] ?? 'Any') ?></td>
               <td data-label="Type" class="lt-text-xs"><?= htmlspecialchars($tpl['type'] ?? 'Any') ?></td>
-              <?php $tp = (int)($tpl['default_priority'] ?? 4); $tChip = match($tp) { 1 => 'lt-chip-critical', 2 => 'lt-chip-warn', 3 => 'lt-chip-info', default => 'lt-chip-ok' }; ?>
-              <td data-label="Priority"><span class="lt-chip <?= $tChip ?>">P<?= $tp ?></span></td>
+              <?php $tp = (int)($tpl['default_priority'] ?? 4); $tBadge = match($tp) { 1 => 'lt-badge-p1', 2 => 'lt-badge-p2', 3 => 'lt-badge-p3', default => 'lt-badge-p4' }; ?>
+              <td data-label="Priority"><span class="lt-badge <?= $tBadge ?>">P<?= $tp ?></span></td>
               <td data-label="Status">
                 <span class="lt-status <?= ($tpl['is_active'] ?? 1) ? 'lt-status-open' : 'lt-status-closed' ?>">
                   <?= ($tpl['is_active'] ?? 1) ? 'Active' : 'Inactive' ?>