fix: some compile time errors

Only 174 errors left!

src/service/rooms/pdu_metadata/data.rs

@@ -1,3 +1,7 @@
+use std::sync::Arc;
+
+use ruma::{EventId, RoomId};
+
 pub trait Data {
     fn mark_as_referenced(&self, room_id: &RoomId, event_ids: &[Arc<EventId>]) -> Result<()>;
     fn is_event_referenced(&self, room_id: &RoomId, event_id: &EventId) -> Result<bool>;

src/service/rooms/pdu_metadata/mod.rs

@@ -1,5 +1,8 @@
 mod data;
+use std::sync::Arc;
+
 pub use data::Data;
+use ruma::{RoomId, EventId};
 
 use crate::service::*;