Replaces copytruncate with rename + `postfix reload` (the same mechanism
`postfix logrotate` itself uses), closing the up-to-one-second window where
copytruncate could drop in-flight delivery lines and leave a send-log row
stuck at "queued" forever.
logrotate-mail.conf keeps `create 0644 root root` rather than `nocreate` as
originally planned: verified on a live container that Postfix recreates the
file itself only lazily, on the next write after reload, and at mode 0600 —
unreadable by the unprivileged panel process. `create` hands the file back at
0644 immediately after rename, before Postfix ever touches it.
logtail.follow() re-drains the old file descriptor once more right before
switching to the rotated file, closing the residual gap between the last
poll's drain and the rotation check. readLogTail() treats a momentarily
missing mail.log as an empty screen rather than a logged error.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
