refactor: Promote handling unsigned data out of timeline

Also fixes:
- Transaction IDs leaking in event route
- Age not being set for event relations or threads
- Both of the above for search results

Notes down concern with relations table

src/api/client/sync/mod.rs

@@ -53,7 +53,7 @@ async fn load_timeline(
 			let last_timeline_count = services
 				.rooms
 				.timeline
-				.last_timeline_count(Some(sender_user), room_id)
+				.last_timeline_count(room_id)
 				.await
 				.map_err(|err| {
 					err!(Database(warn!("Failed to fetch end of room timeline: {}", err)))
@@ -71,12 +71,13 @@ async fn load_timeline(
 			services
 				.rooms
 				.timeline
-				.pdus_rev(
-					Some(sender_user),
-					room_id,
-					ending_count.map(|count| count.saturating_add(1)),
-				)
+				.pdus_rev(room_id, ending_count.map(|count| count.saturating_add(1)))
 				.ignore_err()
+				.map(move |mut pdu| {
+					pdu.1.set_unsigned(Some(sender_user));
+					// TODO: bundled aggregations
+					pdu
+				})
 				.ready_take_while(move |&(pducount, _)| pducount > starting_count)
 				.boxed()
 		},
@@ -86,12 +87,13 @@ async fn load_timeline(
 			services
 				.rooms
 				.timeline
-				.pdus_rev(
-					Some(sender_user),
-					room_id,
-					ending_count.map(|count| count.saturating_add(1)),
-				)
+				.pdus_rev(room_id, ending_count.map(|count| count.saturating_add(1)))
 				.ignore_err()
+				.map(move |mut pdu| {
+					pdu.1.set_unsigned(Some(sender_user));
+					// TODO: bundled aggregations
+					pdu
+				})
 				.boxed()
 		},
 	};

src/api/client/sync/v3/state.rs

@@ -127,7 +127,7 @@ pub(super) async fn build_state_incremental<'a>(
 		let last_pdu_of_last_sync = services
 			.rooms
 			.timeline
-			.pdus_rev(Some(sender_user), room_id, Some(last_sync_end_count.saturating_add(1)))
+			.pdus_rev(room_id, Some(last_sync_end_count.saturating_add(1)))
 			.boxed()
 			.next()
 			.await