feat: add concurrency safety, caption detection, admin enhancements, and performance improvements

app/templates/admin_logs.html

@@ -109,6 +109,22 @@
       <span class="summary-stat summary-stat-failed">失败 <strong>{{ summary_failed or 0 }}</strong></span>
       <span class="summary-stat summary-stat-done">已完成 <strong>{{ summary_done or 0 }}</strong></span>
     </div>
+    {% if failure_breakdown %}
+    <div class="summary-dist" style="margin-top:12px;">
+      <h3 class="section-subtitle">失败原因分布（{{ summary_failed or 0 }} 篇）</h3>
+      <div class="summary-dist-bars">
+        {% set fb_total = (failure_breakdown | map(attribute='count') | sum) or 1 %}
+        {% set error_labels = {"pdf_download_failed":"PDF下载失败","timeout":"超时","process_error":"进程错误","json_not_found":"JSON缺失","json_invalid":"JSON无效","field_missing":"字段缺失","schema_error":"结构错误","unknown":"未分类"} %}
+        {% for item in failure_breakdown %}
+        <div class="dist-row">
+          <span class="dist-label">{{ error_labels.get(item.error_type, item.error_type) }}</span>
+          <div class="dist-bar-wrap"><div class="dist-bar dist-bar-failed" style="width:{{ (item.count / fb_total * 100)|round(1) }}%"></div></div>
+          <span class="dist-count">{{ item.count }}</span>
+        </div>
+        {% endfor %}
+      </div>
+    </div>
+    {% endif %}
     <div id="summary-list"
          hx-get="/admin/summary-status"
          hx-trigger="load"