Improve tracing spans for notif counts and sliding-sync exts.

Signed-off-by: Jason Volk <jason@zemos.net>

src/service/rooms/user/mod.rs

@@ -35,6 +35,7 @@ impl crate::Service for Service {
 }
 
 #[implement(Service)]
+#[tracing::instrument(level = "debug", skip(self))]
 pub fn reset_notification_counts(&self, user_id: &UserId, room_id: &RoomId) {
 	let count = self.services.globals.next_count();
 
@@ -53,6 +54,7 @@ pub fn reset_notification_counts(&self, user_id: &UserId, room_id: &RoomId) {
 }
 
 #[implement(Service)]
+#[tracing::instrument(level = "debug", skip(self), ret)]
 pub async fn notification_count(&self, user_id: &UserId, room_id: &RoomId) -> u64 {
 	let key = (user_id, room_id);
 	self.db
@@ -64,6 +66,7 @@ pub async fn notification_count(&self, user_id: &UserId, room_id: &RoomId) -> u6
 }
 
 #[implement(Service)]
+#[tracing::instrument(level = "debug", skip(self), ret)]
 pub async fn highlight_count(&self, user_id: &UserId, room_id: &RoomId) -> u64 {
 	let key = (user_id, room_id);
 	self.db
@@ -75,6 +78,7 @@ pub async fn highlight_count(&self, user_id: &UserId, room_id: &RoomId) -> u64 {
 }
 
 #[implement(Service)]
+#[tracing::instrument(level = "debug", skip(self), ret)]
 pub async fn last_notification_read(&self, user_id: &UserId, room_id: &RoomId) -> u64 {
 	let key = (room_id, user_id);
 	self.db