Derive Clone for kv::Value?

[SpriteOvO]

Currently the only way to clone a kv::Value seems to be ToValue::to_value(), it limits the downstream kv::Value wrappers to implement Clone.

For example:

// #[derive(Clone)]
struct Wrapper<'a>(log::kv::Value<'a>);

impl Clone for Wrapper<'_> {
    fn clone(&self) -> Self {
        Self(self.0.to_value())
    }
}

First, the wrapper can't directly #[derive(Clone)] as kv::Value does not implement Clone.

Second, the to_value() call raises a lifetime error:

lifetime may not live long enough
method was supposed to return data with lifetime `'2` but it is returning data with lifetime `'1`

I think adding a #[derive(Clone)] to kv::Value should be fine and it solves the problem.