Enhance project structure by reorganizing struct definitions

[nassah221]

This PR includes the quality of life improvements and aren't necessarily related to a particular open issue.

• Move pkg/control/types.go to its own package pkg/types/types.go
• Move Service interface to its own pkg pkg/service
• Move Orchestrator to its own pkg pkg/orchestrator
• Control is now responsible for setting up service and orchestrator in its constructor

Commits can be squashed before merge.

[clone1018]

Feel free to close this!