lei up --all: show output for warnings

This helps users make sense of which saved searches some
warnings were coming from.

Since I often create and discard externals, some warnings
from saved searches were confusing to me without output context:

  "`$FOO' is unknown"
  "$FOO not indexed by Xapian"

1 files changed, 8 insertions, 4 deletions

diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index 51b0e95e..183cb545 100644
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -522,7 +522,7 @@ sub sigint_reap {
 sub fail ($$;$) {
         my ($self, $buf, $exit_code) = @_;
         $self->{failed}++;
-        err($self, $buf) if defined $buf;
+        warn($buf, "\n") if defined $buf;
         $self->{pkt_op_p}->pkt_do('fail_handler') if $self->{pkt_op_p};
         x_it($self, ($exit_code // 1) << 8);
         undef;
@@ -542,7 +542,7 @@ sub puts ($;@) { out(shift, map { "$_\n" } @_) }
 sub child_error { # passes non-fatal curl exit codes to user
         my ($self, $child_error, $msg) = @_; # child_error is $?
         $child_error ||= 1 << 8;
-        $self->err($msg) if $msg;
+        warn($msg, "\n") if defined $msg;
         if ($self->{pkt_op_p}) { # to top lei-daemon
                 $self->{pkt_op_p}->pkt_do('child_error', $child_error);
         } elsif ($self->{sock}) { # to lei(1) client
@@ -588,8 +588,12 @@ sub _lei_atfork_child {
         eval 'no warnings; undef $PublicInbox::LeiNoteEvent::to_flush';
         undef $errors_log;
         $quit = \&CORE::exit;
-        $self->{-eml_noisy} or # only "lei import" sets this atm
-                $SIG{__WARN__} = PublicInbox::Eml::warn_ignore_cb();
+        if (!$self->{-eml_noisy}) { # only "lei import" sets this atm
+                my $cb = $SIG{__WARN__} // \&CORE::warn;
+                $SIG{__WARN__} = sub {
+                        $cb->(@_) unless PublicInbox::Eml::warn_ignore(@_)
+                };
+        }
         $current_lei = $persist ? undef : $self; # for SIG{__WARN__}
 }