Address PR feedback: Add void return test case, simplify clippy logic, remove unrelated files

Co-authored-by: jsturtevant <[email protected]>

Author: Copilot

src/hyperlight_component_util/src/guest.rs

@@ -68,15 +68,7 @@ fn emit_import_extern_decl<'a, 'b, 'c>(
                     ResourceItemName::Static(mn) => quote! { #mn },
                 },
             };
-            // Only emit the allow attribute if unmarshal is not empty
-            let unmarshal_with_attr = if unmarshal.is_empty() {
-                quote! {}
-            } else {
-                quote! {
-                    #[allow(clippy::unused_unit)]
-                    #unmarshal
-                }
-            };
+            // Use unmarshal directly since empty TokenStream generates no code
             let decl = quote! {
                 fn #n(&mut self, #(#param_decls),*) -> #result_decl {
                     let mut args = ::alloc::vec::Vec::new();
@@ -87,7 +79,7 @@ fn emit_import_extern_decl<'a, 'b, 'c>(
                         ::hyperlight_common::flatbuffer_wrappers::function_types::ReturnType::VecBytes,
                     );
                     let ::core::result::Result::Ok(#ret) = #ret else { panic!("bad return from guest {:?}", #ret) };
-                    #unmarshal_with_attr
+                    #unmarshal
                 }
             };
             match fnname {

src/hyperlight_host/tests/wit_test.proptest-regressions

@@ -53,6 +53,8 @@ interface roundtrip {
     enum-a, enum-b, enum-c
   }
   roundtrip-enum: func(x: testenum) -> testenum;
+  // Test case for void return function (no clippy unused_unit warnings)
+  do-something: func(number: u32);
 }
 
 interface host-resource {

src/tests/rust_guests/witguest/guest.wit

@@ -113,6 +113,9 @@ impl test::wit::Roundtrip for Guest {
     ) -> test::wit::roundtrip::Testenum {
         (Host {}).roundtrip_enum(x)
     }
+    fn do_something(&mut self, number: u32) {
+        (Host {}).do_something(number)
+    }
 }
 
 impl test::wit::TestHostResource for Guest {