message: Fix an off-by-one in record parameter allocation
  Summary: Previously we used with_capacity and were 1 short, so it had to do a realloc and complete copy just at the end.
diff: @@ -228,7 +228,7 @@ where
  heap: &'v Heap,
  ) -> anyhow::Result<FunctionInvoker<'v, 'a>> {
  let name = self.typ.as_deref().unwrap_or("record").to_owned();
  - let mut signature = ParametersSpec::with_capacity(name, self.fields.len());
  + let mut signature = ParametersSpec::with_capacity(name, self.fields.len() + 1);
  signature.required("me"); // Hidden first argument
  signature.no_args();
  for (name, field) in &self.fields {
  