style(design): FINDING-004 — add empty state for logs page

When no sync run is selected, the logs page was completely blank
below the controls. Added a guidance message with icon explaining
what to do. Hides automatically when a run is selected.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/app/templates/logs.html

@@ -47,6 +47,13 @@
     </div>
 </div>
 
+<!-- Empty state (shown when no run selected) -->
+<div id="logEmptyState" class="text-center py-5" style="color:var(--text-muted)">
+    <i class="bi bi-journal-text" style="font-size:2.5rem;opacity:0.4"></i>
+    <p class="mt-3 mb-1" style="font-size:0.9375rem">Selecteaza un sync run din lista de mai sus</p>
+    <p style="font-size:0.8125rem">Jurnalele arata detalii pentru fiecare sincronizare: comenzi importate, omise, erori.</p>
+</div>
+
 <!-- Detail Viewer (shown when run selected) -->
 <div id="logViewerSection" style="display:none;">
     <!-- Filter pills -->
@@ -102,5 +109,5 @@
 {% endblock %}
 
 {% block scripts %}
-<script src="{{ request.scope.get('root_path', '') }}/static/js/logs.js?v=14"></script>
+<script src="{{ request.scope.get('root_path', '') }}/static/js/logs.js?v=15"></script>
 {% endblock %}