Split core Client trait into Invoker + WrapLoader + WrapInvoker + UriResolverHandler

[nerfZael]

The Client trait is now defined as follows:

pub trait Client: Invoker + WrapLoader + WrapInvoker + UriResolverHandler {}

The idea being that developers can now define type constraints based only on the traits that they need.
E.g.

• if all function needs is the ability to invoke a URI then it only needs an invoker.
• if it needs to be able to load and invoke wrappers then it needs a WrapLoader + WrapInvoker

The component traits of the Client are defined as follows:

pub trait Invoker: Send + Sync {
    fn invoke_raw(
        &self,
        uri: &Uri,
        method: &str,
        args: Option<&[u8]>,
        env: Option<&Env>,
        resolution_context: Option<&mut UriResolutionContext>,
    ) -> Result<Vec<u8>, Error>;
    fn get_implementations(&self, uri: &Uri) -> Result<Vec<Uri>, Error>;
    fn get_interfaces(&self) -> Option<InterfaceImplementations>;
    fn get_env_by_uri(&self, uri: &Uri) -> Option<&Env>;
}

pub trait WrapLoader: Send + Sync {
  fn load_wrapper(
      &self,
      uri: &Uri,
      resolution_context: Option<&mut UriResolutionContext>,
  ) -> Result<Arc<dyn Wrapper>, Error>;
}

pub trait WrapInvoker: Send + Sync {
  fn invoke_wrapper_raw(
      &self,
      wrapper: &dyn Wrapper,
      uri: &Uri,
      method: &str,
      args: Option<&[u8]>,
      env: Option<&Env>,
      resolution_context: Option<&mut UriResolutionContext>,
  ) -> Result<Vec<u8>, Error>;
}

pub trait UriResolverHandler {
  fn try_resolve_uri(
      &self,
      uri: &Uri,
      resolution_context: Option<&mut UriResolutionContext>,
  ) -> Result<UriPackageOrWrapper, Error>;
}

Additionally, get_env_by_uri has been moved from the Client trait into the Invoker trait. It makes sense that anyone with access to invoker can also get env's just like interfaces and implementations. This is especially true in the full version of WRAP 0.2 where getting those 3 is only possible through invocations.