## Summary
* Remove the usecase-specific and agent-specific observation classes, replacing with a more flexible system
* Add configuration schemas to every observation class
* Add router, firewall, port, and application observation
* Re-shape the dict structure of observations to make it adhere to CAOS 0.8
* Change existing configs to use the new structure
* make host observation separate
## Test process
existing and new unit tests as well as ad hoc notebooks
## Checklist
- [ ] PR is linked to a **work item**
- [ ] **acceptance criteria** of linked ticket are met
- [ ] performed **self-review** of the code
- [ ] written **tests** for any new functionality added with this PR
- [ ] updated the **documentation** if this PR changes or adds functionality
- [ ] written/updated **design docs** if this PR implements new functionality
- [ ] updated the **change log**
- [ ] ran **pre-commit** checks for code style
- [ ] attended to any **TO-DOs** left in the code
Related work items: #2417
e3d3a94da2