engine.py held four unrelated things: what the tables are, how to open a
connection, how to read a database's state, and the Store that coordinates
writes. At 1240 lines the Store's own concerns — locks, migrations, vacuum,
tags — were hard to find among them.
Table records, Arrow schemas, index_specs, ensure_indexes, REQUIRED_TABLES
and query_to_pydantic move to store/schema.py, which imports nothing from
haiku.rag: it describes the tables and never opens or mutates one.
gather_database_info, get_database_stats, DatabaseInfo and its result models
move to store/info.py. Nothing in Store calls them — they are read paths for
the CLI, doctor, inspector and ingester API — so info depends on engine and
not the reverse.
engine.py keeps the Store, ConnectionMode, connect_lancedb, the tag helpers
and the restore-order and retention constants. No re-exports: importers
point at the new modules.
test_app_info_uses_connect_lancedb_for_remote patched
haiku.rag.store.engine.connect_lancedb; gather_database_info now binds that
name in info.py, so the patch targets where the call is looked up.
