Handle not read control interface messages in agent

[inf17101]

Currently, the swdd is not implemented and tested: swdd~agent-handles-control-interface-input-pipe-not-read~1

There is the part missing that prevents overwhelming the workload with messages.

Tasks:

• [ ] Analyze which parts of the swdd are already implemented and not
• [ ] implement the missing functionalities of the swdd
• [ ] test the impl
• [ ] link the swdd to fix the uncovered state