In this PR:
1. Implement application-specific functionalities in the
`DataHavenServiceManager` contract:
1. Registering of 3 operator sets: Validators, BSPs and MSPs.
2. Allowlisted sign up of operators.
3. Integration with Snowbridge to send message of new validator set.
2. Basic testing of the above functionalities.
3. Tests now use less mocked contracts (especially from EigenLayer).
4. Refactor of `SignUpOperator` script, which now supports the three
kinds of Operator sets.
