Rework Wasm interface

src/bin/scryer-prolog.rs

@@ -1,3 +1,7 @@
 fn main() -> std::process::ExitCode {
-    scryer_prolog::run_binary()
+    #[cfg(target_arch = "wasm32")]
+    return std::process::ExitCode::SUCCESS;
+
+    #[cfg(not(target_arch = "wasm32"))]
+    return scryer_prolog::run_binary();
 }