add option to recompute room state

Hopefully we can make use of this state resolution code for more stuff
in the future.

src/cli/get_room_states.rs

@@ -13,6 +13,7 @@ use crate::{
 };
 
 mod cache;
+mod recompute;
 
 /// Serializable information about a state event
 #[derive(Serialize, PartialEq, Eq)]
@@ -63,7 +64,11 @@ pub(crate) async fn run(
 
     db.apply_migrations().await.map_err(Error::Database)?;
 
-    let room_states = cache::get_room_states().await;
+    let room_states = if args.recompute {
+        recompute::get_room_states(db)
+    } else {
+        cache::get_room_states().await
+    };
 
     serde_json::to_writer(std::io::stdout(), &room_states)?;