ui(panel): homepage drops 上次 column, keeps 下次执行 + 最近运行

上次 trigger time duplicated 最近运行's log mtime — remove it (column now
just 下次执行) along with its log-mtime backfill in index().

web/app.py

@@ -640,11 +640,6 @@ def index():
             nxt = _next_fire(times, now)
             if nxt:
                 s["next"] = nxt.strftime("%m-%d %H:%M")
-        # 同理,上次触发用最近一次运行日志的时间(launchd 不提供)
-        if s.get("last") in (None, "", "-", "从未触发"):
-            mtime = (s.get("log") or {}).get("mtime", "")
-            if mtime:
-                s["last"] = mtime[5:]  # "2026-10-23 17:18" → "10-23 17:18"
     # digest timer 状态
     digest_props = get_systemd_props("news-harvester-digest.timer")
     digest_run_time = (read_oncalendar_from_systemd("news-harvester-digest.timer")

web/templates/index.html

@@ -47,7 +47,7 @@
       <th>状态</th>
       <th>运行时间</th>
       <th>Provider</th>
-      <th>上次 / 下次触发</th>
+      <th>下次执行</th>
       <th>最近运行</th>
       <th>操作</th>
     </tr>
@@ -96,8 +96,7 @@
         {% endif %}
       </td>
       <td>
-        <span style="color:#666;font-size:12px">上次</span> {{ s.last }}<br>
-        <span style="color:#666;font-size:12px">下次</span> <span style="color:#e8c34a;font-weight:600">{{ s.next }}</span>
+        <span style="color:#e8c34a;font-weight:600">{{ s.next }}</span>
       </td>
       <td>
         {% if s.source in active %}