feat(cli-tools): Add internal operator and sponsorship commands

[teogeb]

Added these internal commands:

• sponsorship-sponsor
• operator-deletage
• operator-undeletage
• operator-stake
• operator-unstake

Also refactored some operatorContractUtils method signatures: user authentication is passed as Signer instead of Wallet, so that client.getSigner() can be used as an argument.

TODO

• Test manually

Future improvements

• These commands could be normal CLI tools commands, i.e. just not for the internal use. That would be possible if we add support for DataV2 token to the SDK. Currently the only token contract available for operatorContractUtils is the test token contract. (Note that most likely there is no need to have both the DataV2 and TestToken, as DataV2 can be used also for tests.)