Emit events for catching staking operation's status

[edisonz0718]

Description and context

Since all our states are in the consensus layer and we only use the staking contract for trigger the staking operations. Users that use our staking operations cannot get the status of their staking operations right away. We need to track the staking operation status in events so that users can check if their staking operations are successfully executed

Suggested solution

Need more investigation and design.

Definition of done

Solution designed , implemented and tested