message: Make Dict::get_str_hashed public
  Summary: No reason not to let people use it. I plan to delete the only use of it internally, but it seems useful to keep rather than delete.
diff: @@ -283,7 +283,8 @@ impl<'v> Dict<'v> {
  self.content.get(&ValueStr(key)).copied()
  }
  - pub(crate) fn get_str_hashed(&self, key: Hashed<&str>) -> Option<Value<'v>> {
  + /// Like [`Dict::get_str`], but where you already have the hash.
  + pub fn get_str_hashed(&self, key: Hashed<&str>) -> Option<Value<'v>> {
  self.content
  .get_hashed(Hashed::new_unchecked(key.hash(), &ValueStr(key.key())))
  .copied()
  