Add ReportServ, wired into the audit trail

Any user can REPORT <nick|#channel> <reason>; filing is rate-limited per
reporter. Reports are an event-sourced, federated queue operators review
with LIST / VIEW / CLOSE / DEL. The interconnection: because a filed report
is an event, the engine's audit feed already announces it to the staff
channel and records it in the searchable action log — so OperServ
LOGSEARCH finds a report by any word in it, tying reports into the same
trail as bans, kicks, and everything else. Opt-in (add "reportserv").

src/grpc.rs

@@ -173,6 +173,9 @@ fn to_wire(entry: &LogEntry) -> Option<ReplicationEvent> {
         | Event::ChannelOperNoteSet { .. }
         | Event::NewsAdded { .. }
         | Event::NewsDeleted { .. }
+        | Event::ReportFiled { .. }
+        | Event::ReportClosed { .. }
+        | Event::ReportDeleted { .. }
         | Event::OperGranted { .. }
         | Event::OperRevoked { .. }
         | Event::SessionExceptionAdded { .. }