refactor: split large modules and normalize rust layout

server-rs/crates/spacetime-module/src/big_fish.rs

@@ -0,0 +1,11 @@
+mod assets;
+mod events;
+mod runtime;
+mod session;
+mod tables;
+
+pub use assets::*;
+pub(crate) use events::*;
+pub use runtime::*;
+pub use session::*;
+pub use tables::*;