- facade storage session manager: project handles bind to the default
SQLite library on project_new/load; every undo push/group_end/jump
write-throughs via DatabaseBackend::save (diff journal); project_free
flushes and unbinds
- background snapshot thread (Storage/SnapshotIntervalSec, latest-wins,
newest 3 kept) with exit flush (oakengine_storage_flush)
- config-gated: storage only activates with an explicit
Storage/Backend=sqlite, so headless consumers and tests never touch
the real library; new exports: storage_flush/is_bound/last_error
- it_storage: kill -9 recovery, cross-session undo, snapshot pruning,
multi-project isolation, graceful degradation
- also fixes a real config test polluting the user config.ini and the
undo-stack test races
Mike-Solar
5fabad8efd