Run archive

The run archive is the directory one explain run persists: manifest.json, base_generation.txt and an SQLite database archive.sqlite (WAL journaling, schema version 4) with one row per coalition evaluation: key, packed mask, policy, model, timing, the generated text and its token logprobs (NULL when the backend returned none). A completion marker distinguishes finished runs. It lets Reanalyze re-score the run without the model.

Identified by the Run id; described by the Manifest. Fixed issue: C02.