[Diags] Begin designing diagnostics backend infrastructure for Phase 2

### Is your feature request related to a problem?

TBD

### Describe the solution you'd like

- [ ] Implement directory normalization with zppy and mache
- [ ] Decide if information needs to be stored in PostgreSQL database for organization, persistence, and to deliver information to the frontend, or query directly from fileserver

### Describe alternatives you've considered

_No response_

### Additional context

_No response_