fix(spaces): add early is_enabled() check in join path, use err! macro

Skip lock acquisition on every join when feature is globally disabled.
Use conduwuit::err! macro instead of manual Error::Err construction.

src/admin/space/roles.rs

@@ -51,9 +51,7 @@ macro_rules! custom_state_pdu {
 		PduBuilder {
 			event_type: $event_type.to_owned().into(),
 			content: to_raw_value($content).map_err(|e| {
-				conduwuit::Error::Err(
-					format!("Failed to serialize custom state event content: {e}").into(),
-				)
+				conduwuit::err!(Err("Failed to serialize state event content: {e}"))
 			})?,
 			state_key: Some($state_key.to_owned().into()),
 			..PduBuilder::default()

src/api/client/membership/join.rs

@@ -347,7 +347,11 @@ pub async fn join_room_by_id_helper(
 		}
 	}
 
-	let parent_spaces = services.rooms.roles.get_parent_spaces(room_id).await;
+	let parent_spaces = if services.rooms.roles.is_enabled() {
+		services.rooms.roles.get_parent_spaces(room_id).await
+	} else {
+		Vec::new()
+	};
 	if !parent_spaces.is_empty() {
 		let mut qualifies_in_any = false;
 		for parent_space in &parent_spaces {

src/service/rooms/roles/mod.rs

@@ -216,9 +216,7 @@ pub async fn ensure_default_roles(&self, space_id: &RoomId) -> Result {
 	let pdu = PduBuilder {
 		event_type: ruma::events::TimelineEventType::from(SPACE_ROLES_EVENT_TYPE.to_owned()),
 		content: to_raw_value(&content).map_err(|e| {
-			conduwuit::Error::Err(
-				format!("Failed to serialize SpaceRolesEventContent: {e}").into(),
-			)
+			conduwuit::err!(Err("Failed to serialize SpaceRolesEventContent: {e}"))
 		})?,
 		state_key: Some(String::new().into()),
 		..PduBuilder::default()