Merely pruning mail synchronization information was
insufficient for Maildir: renames are common in Maildir
and we need to detect them after-the-fact when lei-daemon
isn't running.
Running this command could make "lei index" far more
useful...
v2: close R/O mail_sync.sqlite3 dbh before fork
Keeping the DB file handle open across fork can cause bad things
to happen even if we don't use it since sqlite3 itself still knows
about it (but doesn't know Perl code doesn't know about it).