feat: restore source parity and harden agent runtime

backend-fastapi/online_dev/document_generator/templates/elements/table.html

@@ -0,0 +1,16 @@
+<table class="element-table">
+<thead><tr>
+{% for col in columns %}
+<th style="width: {{ col.width|default('auto') }}">{{ col.label }}</th>
+{% endfor %}
+</tr></thead>
+<tbody>
+{% for row in rows %}
+<tr>
+{% for col in columns %}
+<td>{{ row[col.field]|default('') }}</td>
+{% endfor %}
+</tr>
+{% endfor %}
+</tbody>
+</table>