chore: clean up core crate

crates/signed_core/src/inbox/mod.rs

@@ -0,0 +1,9 @@
+mod group;
+mod item;
+mod read_state;
+mod resolver;
+
+pub use group::group;
+pub use item::InboxItem;
+pub use read_state::InboxReadState;
+pub use resolver::ThreadResolver;