Incorrect Java code generated for verbs with primitive response type

[tomdaffurn]

When a Java module depends on a verb with primitive response type, and non-primitive param type, the generated Java verb client doesn't compile.

The generated client should use boxed types instead of primitives to match the xyz.block.ftl.VerbClient interface.

This verb:

//ftl:verb export
func TheVerb(ctx context.Context, val string) (int, error) {
    return 1, nil
}

Creates this generated client:

@VerbClientDefinition(
    name = "theVerb",
    module = "example"
)
public interface TheVerbClient extends VerbClient<String, Long> {
  long call(@NotNull String value);
}

Compilation of this client fails with:

[ERROR] <module>/TheVerbClient.java:[13,8] call(@org.jetbrains.annotations.NotNull String) in ftl.example.TheVerbClient clashes with call(P) in xyz.block.ftl.VerbClient
[ERROR] return type long is not compatible with java.lang.Long