Gated by DECNET_DEVELOPER_TRACING env var (default off, zero overhead).
When enabled, traces flow through FastAPI routes, background workers
(collector, ingester, profiler, sniffer, prober), engine/mutator
operations, and all DB calls via TracedRepository proxy.
Includes Jaeger docker-compose for local dev and 18 unit tests.
- Add `get_repository()` factory function to select DB implementation at runtime via DECNET_DB_TYPE env var
- Extract BaseRepository abstract interface from SQLiteRepository
- Update dependencies to use factory-based repository injection
- Add DECNET_DB_TYPE env var support (defaults to sqlite)
- Refactor models and repository base class for cross-dialect compatibility
