sync upstream spaces/hierarchy federation MR

also had to fix a million clippy lints

fix(spaces): deal with hierarchy recursion
fix(spaces): properly handle max_depth
refactor(spaces): token scheme to prevent clients from modifying max_depth and suggested_only
perf(spaces): use tokens to skip to room to start populating results at
feat(spaces): request hierarchy from servers in via field of child event

Co-authored-by: Matthias Ahouansou <matthias@ahouansou.cz>
Signed-off-by: strawberry <strawberry@puppygock.gay>

src/service/rooms/state_cache/mod.rs

@@ -293,6 +293,7 @@ impl Service {
 		self.db.room_members(room_id)
 	}
 
+	/// Returns the number of users which are currently in a room
 	#[tracing::instrument(skip(self))]
 	pub fn room_joined_count(&self, room_id: &RoomId) -> Result<Option<u64>> { self.db.room_joined_count(room_id) }
 
@@ -310,6 +311,7 @@ impl Service {
 		self.db.active_local_users_in_room(room_id)
 	}
 
+	/// Returns the number of users which are currently invited to a room
 	#[tracing::instrument(skip(self))]
 	pub fn room_invited_count(&self, room_id: &RoomId) -> Result<Option<u64>> { self.db.room_invited_count(room_id) }